I can see it already detracting into the "what constitutes as a viable Native American mascot name" which is how these get so off topic that threads get shut down.
Should really try to keep it on the possible names rather than other teams, the "why" and other things that lead to those conversations.
As far as name speculation so far, I do like Warriors even if it's generic/basic/simple/expected. Redtails just doesn't seem to work for me. I think Americans could work but you run into the issues bring up about the Nationals existing, why Seattle won't choose Metropolitans, etc. Redwolves is certainly a hot runner that seems to have come out of knowwhere. It'd be great if they could resurrect Federals. But being a USFL team, you know there'd be bad blood there due to the lawsuit. Generals would be good and I recall hearing that the Globetrotters would be willing to sell it. But literally being the identity of a team designed to lose, as funny as it'd be, I doubt the NFL team would want that history.
Another thought as far as DC-related could be Monuments or Representatives (Reps). As much as Potomacs sounds great, it still leads to Native American territory and they should be as far away from that as possible.
It's going to be exciting speculation to see what they come up with!