Lord, I used to love St. Anthony's for the noon Masses and round the clock Confessions. I stopped working in Boston when my daughter was born in 1989 and when I returned periodically for shopping visits I would always visit St. Anthony's for a quick thank you along with my babies in the stroller. It slowly devolved and now I don't even bother visiting there, too sad. The Paulist Center is nutty and has been since I was a young teenager in the early 1970s.
An absolute *GEM* that I found years ago is the St. Thomas More chapel at 49 Franklin St. - maintained by the Propagation of the Faith. It's between Filene's and the old Woolworths (TJMaxx now I think) building, on the Filene's side walking towards Post Office Square -- a couple of buildings behind Filene's.
The other wonderful 'stop in chapel' is the one at the Pru on the bottom floor, St. Francis - kind of modern, but very, very orthodox. Excellent little bookstore as well. It's staffed by the Oblates of the Virgin Mary.
I never heard of the St. Thomas More chapel -- and I've been down Franklin Street a lot! What does the entrance look like?
As for Arch Street, I was going to their 8:30, 3 or 4 years ago, I think, and that was quite sedate -- even novena prayers Tuesdays and Thursdays (one for St. Jude and one for St. Anthony -- I forget now which was which, and with veneration of a relic of St. Anthony on his novena day), no lectors, and another Friar or a Brother would help with Communion.
Even at that time, though, I went to the noon Mass once, and it was pretty far gone for my taste -- the progressive laity were apparently in charge and lapping it up!
Unfortunately, the 8:30 was one of the first Masses cut.