If there is justice in this world, that lifeforce-sucking busway will get killed off by a lawsuit from Newington and West Hartford over the destruction to be wrought by the ramps scheduled to be built on the Amtrak ROW. It's the worst-kept secret in the world that West Hartford is trying to find every legal loophole it can look for to launch the killshot. Perhaps the only transit project in the country a more senseless waste than South Coast Rail.
-- New Milford extension of the MNRR Danbury Line is an actual proposal with solid, solid fundamentals:
http://www.danburybranchstudy.com/. Separate that one out from the Caanan/Pittsfield proposal, which is by the private Housatonic RR. Brookfield and New Milford have been suffering for decades from the cancellation of the US 7 expressway. This is easily the #3 passenger rail extension priority in-state behind New Haven-Hartford-Springfield and Shore Line East to Westerly, RI.
-- Forgot the Bradley Airport spur on your map. That's an official appendage to the NHHS proposal. Although, really, until there's some multiple service configurations out there I'm not sure a "dinky" on that line is going to offer any advantage over a shuttle bus from the mainline stop.
-- If the @#$% busway would just die-die-die, "New Britain loop" service on NHHS would be good and cheap. Divert up from Berlin, return to the main on the NB Secondary. Route every third NHHS train that way.
-- Speaking as a Bristol native, Hartford-Waterbury commuter rail would be quite very well patronized. That one needs to happen. Although it's going to be hobbled if it has to use the Berlin Branch because the godawful busway is hogging the New Britain Secondary. Has had consensus political support for years...the DOT is just drinking the BRT kool-aid by the metric ton.
-- Hartford-Manchester/Vernon is a quickie on active track that would be very beneficial to do. Hartford, East Hartford Ctr., Buckland Hills, Manchester Ctr., Vernon/Exit 65 would be well-patronized. Only about a mile of abandoned track between end of the freight line and Exit 65 to put back. I'd rank that behind NHHS, New Milford, and Hartford-Waterbury. Could work as an east terminus for Waterbury-Hartford so there's an "I-84 line", or DMU's would work well on a short shuttle.
-- Obviously the Willimantic gap needs to be filled. State's flagged that a high-priority future consideration in the official State Rail Plan. "Suicide 6" is not going away as one of the most acute road problems in the state, it's a bona fide commuter rail market with the easy continuing connection to New London, and it's the only way to link UConn to the rest of the state on public transit. Only question is where. I think passing on the landbanked ROW in favor of rail on the I-384 extension "greenway" median is the way to go. Dust off the proposal that was fed fast-tracked from 2001-04 before the Army Corps played politics and spiked it, and put rail on the 1000 ft. median. Grade the curves to support future Inland NEC speeds, and open it as a regular 80 MPH diesel line with double-stack freight clearances (opening up a crucial Hartford gateway for the oversize freight NECR and P&W already move to Willimantic). That gives the whole deal enough environmental mitigation juice to placate the Army Corps., and achieves cost efficiency by doubling-up the rail and highway in one EIS.
-- The Eastern CT proposal for service on the NECR main from New London to Willimantic is a real one. And running hot at the moment. NECR is privately dangling that one right now in conjunction with the local Chambers of Commerce and MPO's. They want it because of the freight track improvements it'll buy them, but they're offering to buy some passenger cars and run it themselves because they think there's a little bit of revenue to pinch from the giant casino bus business. NECR runs directly alongside Mohegan Sun and has 60 MPH track:
http://goo.gl/maps/lZnZo. Limited service here with the public-private partnership would get it entrenched enough to up the demand for the Manchester-Willimantic connection to be restored and bona fide Hartford-New London commuter rail (Route 2 commuters just got a faint twinkle in the eye at that thought).
-- P&W is making goo-goo eyes at the state for getting passenger service on its east-of-river New London mainline, so that's a real proposal too. There used to be a Worcester-bound intercity train that used this line through Day 1 of Amtrak before it got cut. Like NECR, this is good 60 MPH track. Unfortunately 395 is well below capacity, Norwich is also hit by NECR, and there isn't potential for a direct casino stop here. But New London-Worcester is pretty intriguing--and inexpensive--as a future consideration.
-- Not on your map, but possibly worth considering as a DMU line: the Griffin Secondary, Hartford-Bloomfield. This was a light rail proposal for almost 20 years until killed in the 90's. Splits the difference between 2 of your streetcar lines and could have a direct U Hartford campus stop. The state has earmarked ROW from back in the light rail proposal days from the end of the line in Bloomfield, across the Farmington River, and on power line land which it could purchase to bring the line to Bradley Airport and connect to the stub end of the Bradley Branch. It's still an active freight proposal, albeit low-priority. If the Bradley connection were made contiguous then that becomes a pretty nice-looking Hartford-Windsor Locks shuttle serving the canceled I-291 corridor and some dense residential in Hartford and Bloomfield. Low-low priority but I think a better future consideration than the streetcars or those redundant CT River-hugging commuter lines.
Those are the ones that are grounded in some decent 20-year reality. I don't think these are going to have much juice:
-- Torrington extension of Waterbury Branch. Route 8 is free-and-clear north of the I-84 interchange. It's an easy drive to Waterbury station from Torrington. There'd be slightly more of a market for Torrington-Hartford because 84 is such a nightmare, but the only way to swing that one is a reverse move at Waterbury. Naugatuck RR runs some very nice excursion service on this line through pretty country, so the line is a going passenger concern. But the potential CR market here is very minimal. Nothing at all like Waterbury-Hartford.
-- Beacon Line, west-of-Brewster. Take one look at how twisty this line is and some of the godawful grade crossings on it. There is no way possible that Metro North could ever run branchline service on this thing and keep any semblance of schedule order on the Hudson or Harlem lines. It's been studied. The ridership is dubious for how constrained the infrastructure is. Also keep in mind that the "advocacy" for Beacon Line commuter rail pretty much boils down to ONE guy who runs a half-dozen websites pushing the idea and spams RR.net and every media outlet comments section to oblivion about how this thing's got real momentum. He's a little...off in the head. But is damn prolific.
-- Middletown Secondary commuter rail. Too close to the Springfield Line, and other than the traffic light clusterfuck in downtown Middletown (which could be fixed ASAP if businesses in downtown didn't keep blocking the grade separation) Route 9 operates slightly below capacity from Berlin to Old Saybrook. Will see much heavier freight traffic in the future as a diversion to Springfield Line traffic.
-- Valley Line/Old Saybrook commuter rail. Same deal...CT 9 just isn't that bad a highway. And a thru-routed NHHS/Shore Line East train that covers Hartford-New Haven-Old Saybrook will get there faster on straight fast track than the twisty Valley Line. No need whatsoever for this. However, if the out-of-service segment of the Valley in Higganum gets reactivated (planned, but state has no money) the Essex Steam Train wants to extend its service to Middletown and run excursions straight to Hartford. Which'll be really nice. That's a very popular tourist line as-is.
-- Air Line/Middletown-Willimantic. Total nonstarter. This route failed the first time around for good reason...totally skips all the population density. "Right-angle" trips off the Springfield Line NH-HFD-WIL are probably gonna be faster anyway when Springfield gets speed-boosted >90 MPH.
-- Maybrook Line, Danbury-Derby. Twisty line, inadequate pop density because it hugs the river inside a linear state park for too much of the distance. The old segment from Derby-New Haven is long-abandoned, so it's also a lot more indirect a route out of NH than it used to be. Good freight bypass for the New Haven Line...P&W was fighting Housatonic RR in court for them to fix up their damn track so it's a sought-after chess piece amongst freight competitors. But that's all it's good for. Nonstarter for passenger.
-- Danbury-Caanan/Pittsfield is an actual proposal from Housatonic RR. But it's a laugher. The Berkshire Line needs >$100M in repairs for subsistence-level freight service, and nobody wants to touch Housatonic because they're a largely discredited outfit. CT and MA both canceled all TIGER grant apps in the queue for Housatonic out of concerns they'd just pocket the money and fuck off. This line is so far in the hole on state of good repair it's going to take a generation before passenger upgrade costs look remotely palatable (beyond the MNRR New Milford extension). MNRR would almost be better off rebuilding the totally abandoned Harlem Line back to Chatham than touching this mess. Really don't think this is a good one at all.
-- Beacon Line, Brewster-Danbury. Housatonic RR has been pitching a plan for service here. Also a laugher, because Housatonic has napalmed so much goodwill launching petty spats with MNRR that the chances of them EVER being allowed on the platforms at Danbury and Southeast are nil. So much ill will seeded by their Internet Tough Guy V.P. of Business. If there's any justice that carrier will be out of business in a year and somebody competent like P&W will scoop up their territory for a song. Brewster-Danbury would be very convenient for alt Danbury service patterns from the MNRR Harlem Line if the wye at Southeast station were restored, but Metro North has studied it and the interest level from Harlem Line commuters is minimal. Money much better spent on spiffing up the Danbury Line. However, this is a much more viable future consideration than the west half of the Beacon Line because it's at least grade-separated, mostly straight, and offers pretty straightforward connectivity.
-- I do not see streetcars returning to Greater Hartford at all, or the need for it. Most of their transit needs can be better served by making CT Transit a less-shitty bus system and providing good commuter rail connections. The route coverage is pathetic. It's got at least 2-3 more gears it can reach for.
-- New Haven and Bridgeport are mulling their streetcar plans, but in NH's case it's a beltline type thing. Too much wishful thinking that either are going to have anything resembling a real network in place. Like Hartford both cities would benefit from less-shitty bus coverage. And they're still too car- and parking lot-centric to realize the upside of a halfway-extensive build like Providence would. Too much wishful thinking here.
-- Not on your map, but I'd also avoid the Armory Line East Hartford-Suffield. That was a slightly laughable BRT proposal in the 90's back when the line was mothballed for freight. Even closer to the Springfield Line than the Middletown Secondary, and if MA reconnects the abandoned portion from the state line to Springfield (which CT and Amtrak badly want) it'll become the primary freight bypass to Hartford and a double-stack route.
Note also: the Inland HSR proposal does use the existing Manchester Secondary at least to Vernon because that's the old intercity route and was built straight, mostly grade-separated, and high speed. Also is slated to use the New Britain Secondary and existing ROW to Waterbury because that was the former high-speed route. The only nightmare there is the downtown Bristol hairpin, which would have to be tunneled-under with a bypass (good luck with that). I still think the feds are smoking crack if they think they're going to be able to plow through from Waterbury to Sandy Hook to reconnect it all. The community opposition is going to be severe out there, and more severe still in Westchester County. East-of-Hartford...yeah, they're in solid shape esp. if it can get bootstrapped on the 384 extension. But this whole vision is going to have to be Springfield Line or bust. The hurdles are just too great out west.