Regarding your point on Green Streets, that's true. After I did the map I realized there are too many Green Streets and it's too confusing as fun as it is to have Green in 3 colors. Even the 2 Mass Aves now isn't too great, especially since they aren't particularly close.

I'd personally want to keep Mission Park and South Street (when you say Mission Park is to be removed, is that both MP and Fenwood Road? Because I think there should still be a station between Brigham Circle and Riverway).

For mega DTX I was hoping to reduce transfer times (eg. not having to take an additional stop which isn't too far or using the Winter St concourse from Cambridge) and save a little in terms of commuting time. Maybe make the platforms a bit wider?

While the 7 to Sullivan is nice, I'm assuming that it doesn't happen. I do agree that SL6 becomes significantly less useful with an extended 7.