The international 757 routes (e.g. PHL to EDI) are probably gone until they take possession of A321LRs with lie-flat seats in the front.
A lot of the routes out of PHL and MIA that were having trouble filling a 767 with 209 seats probably won't be able to fill a 788 with 239 seats (and some of those are W seats which the 767s never got). Depending on how fast vacation demand to Europe comes back, AA might have to think long and hard about its PHL strategy as a European hub.
The 772 is going to be way too big a plane for a lot of their routes, so I can see that being relegated to LHR, CDG, HKG, HND, SYD, and some cargo routes that require a 77W. I think SEA-BLR will happen, mainly because they need to try some long and skinny routes to justify the 789s, otherwise they'll just end up flying them to CUN. The trick is not running into the trap Delta ran into in SEA -- it's geographically convenient for Asia, but folks from LAX and SFO, who are most of the passengers that you are going to connect through SEA, have several non-stop options, or will fly JL/NH/CX with a connection in Asia.