Limping AA in early position can be a good play, and it sounds like you know when the right times to do this are. Definitely not good at a loose passive table, but when you are hoping for a raise, it can really get people tied to their hands. Its always good to keep your plays varied.

If that backdoor flush scare card does fall (or any other scare cared), its sometimes better to just check the river since a big bet will usually be folded to unless they have the flush (sometimes other big pocket pairs will call as well). Anyways, if he doesnt have anything decent he will just fold. If you check, you might get a bluff from weaker hands. If he checks behind, well, he probably would have folded anyways. Smaller, call-able river bets also work sometimes.

Just be prepared for more suckouts when flop checking AA like this, and be able to fold when beat.