Didn't realize I had two usernames on here...
Got a few suggestions...
KDRO
Durango-LaPlata County Airport, Durango, CO
KFSM
Fort Smith Regional Airport, Fort Smith, AR
KBIL
Billings Logan International Airport, Billings, MT
KGPT
Gulfport-Biloxi International Airport, Gulfport, MS
KAEX
Alexandria International Airport, Alexandria, LA
KLFT
Lafayette Regional Airport, Lafayette, LA
I realize a few of these may be too big to do for just freeware scenery, but they're just my humble suggestions, after all :-) Thanks for doing any airports, we know you don't have to and it's greatly appreciated.