Westfield pretty firmly slots in the local commuter category. If this were a commuter rail line you'd absolutely see a stop there, and in Wilbraham on the east side of Springfield too. But those are mostly folks looking to transfer to the Hartford Line or possibly a Hartford Line run-thru commuter service flavor that covers the Conn River Line to Northampton/Greenfield. And for matching to those frequencies they already have pretty good PVTA bus route coverage to get them 8 miles over to Springfield Union. An Amtrak schedule is utterly non-useful for that, and since these towns have never been stops on the intercity coach buses' Springfield routes the patronage at an intermediate stop for Amtrak-only would be utterly microscopic. Unfortunately the E-W B&A corridor doesn't run dense enough far enough on either side of Springfield to outstretch the PVTA district in any distinctly useful way with Springfield-spanning commuter rail, so the answer to all demand questions here is to simply increase PVTA frequencies and give them outright more cracks at SPG Hub transfers rather than work the rail angle to bottom-barrel returns.Regarding the route and ridership of the East West. Why wouldn't they include a station stop in Westfield, a city of over 40,000 people? It looks like almost an hour by bus but it only 10 miles away.
The Palmer infill is somewhat distinct in that CT/MA Route 32 is probably the most significant highway corridor in all of Southern New England served only by a two-lane local highway with absolutely nothing limited-access in a 15-mile radius of it on either side. UConn & UMass + the Amherst-area colleges all funnel on that route, and you've got the only halfway-significant Worcester Hills/Eastern CT "Quiet Corner" population centers like Ware, Barre, Stafford Springs, Willimantic pooling onto that route. The Pike exit basically splits the MA and CT "halves" of that corridor right at the midpoint, so ends up an insanely convenient place to run a University shuttle bus or kiss-and-ride for making an intercity connection. The projected ridership stakes are small overall compared to what all other stops on the Inland Route or other Springfield Hub route combos generate, but the catchment area is so vast because of 32's quirky positioning as Southern New England's last real "not-a-highway" highway corridor with all of it woefully under-served by all current forms of transportation so it ends up a valuable add.