I agree wholeheartedly.So why not rezone the rest of it now and revise (upwards) the remaining residentials? There are plenty of parcels remaining and the demand to go bigger, especially with the ongoing housing crunch.
Unfortunately that process is not as easy as any of us would wish.
We all have the ability to look at things with perfect hindsight.
This is why I take offense (only mild) when people complain and say Ink Block should have been bigger, taller, etc.
Folks love to forget how big of a risk that development was at the time. It led to everything around it going bigger, but it gets unfairly beat up when people put their historical blinders on.
I wouldn't stop with just the residential.
I've argued on taller labs, but will leave that for now.
The office crunch in Cambridge is pretty bad as well. There's no reason to keep office buildings as squat (or squatter, H is office and G is lab, yet G is taller) as zoning allows.