i do believe Back Bay can handle about 5~6 >200m towers, and about 5~6 >180m towers to go along with all the 90-110m low highrises currently permitted or proposed, and still keep it's charm and unique character. But that's about it. That's a good practical limit... To pay for Back Bay Station, they should have shot for 180m/600' on one of the towers.
Sigh.
Just move to NY or something already.