While I was in Miami I got to use the transit system as well. Mixed mode and somewhat unreliable. Could certainly use a LOT of expansion to more suburbs, but I like the idea of the peoplemover, at least it's something that many other US metros could replicate.

Also recently travelled to Washington DC
While most of the time I spent using ride share and walking, I will say that the architecture of the metro is absolutely marvelous. I got the opportunity to ride from the national Mall area to Reagan. Would love to see more routes around DC next time.

Recently travelled to Boston
I was quite impressed with the public transit downtown.
Huge step up from what I've seen in Florida. I do think that Boston could greatly benefit with a ring route a la the yamanote line.