Racedo,
Sorry I just picked up on this one. It really depends what you like. Civil and Mail? Clean, neat, clinical presentation or meaty historic goodies? How old (WW1? WW2?)?
I've not seen so many and if you use Pima as a benchmark as you say you went there, there are lots of others with a wealth of interesting exhibits that also portay the international nature of aviation. I'm a Brit and I'd agree that Hendon is great, and so is the site at Duxford where, on a show day, you'll see a lot of oldies in action, but I apppreciate and relish the idea of out-of-the-way places with unusual exhibits. I'd offer Belgrade Aviation Museum at the Airport, Brussels National Musuem, Kiev-Zhulyany, Cuatro Vientos in Madrid. There are lots more. I'd recommend searching on the net a little.....
Good luck!
RR