Posted this earlier, but made some errors and decided to take my time on it. I've made some pretty major improvements, and now I'm very happy with it. My AI traffic is made up of models from AIA, AIM, AIG, TFS, and FAIB, etc, with flightplans from the good folks at the Alpha India Group. Parking radius' are mostly standard, the ExpressJet parking may be a bit wider than needed. Some parking codes have been added to accommodate older AI traffic (like BTA at Terminal B) this doesn't effect standard UALX aircraft's parking selection. Remote stands also have some 'dummy' codes in them to knock their priority down from standard terminal gates.
I refined, and added a lot that slipped my mind initially.
Biggest thing though, I shorted runway 26R and 15L to force large aircraft to take 26L or 27 (depending on direction of flight), and 15R (for departures), while the ERJs, and CRJs use 26R for arrivals and 15L for departures.
Runway selection depends on your AI traffic having the appropriate "empty_weight=" values in their aircraft.cfg, I didn't edit any of my AIA, FAIB, AIM, AIG, TFS, UTT models, and everything worked out just fine, so as long as you have the standard "empty_weight=" values you should be good. Another note, I deleted two small portions of taxiway just west of 15L to prevent AI from trying to cross 15L to get to 15R, this allows them to continue north on WB, join NB to bypass the traffic jam at 15L.
This isn't ideal, but it's certainly better than all the traffic piling up on 26R and 15L. It is realistic though, with regards to operations. Only thing not realistic is Lufthansa's A380 departing 15R, I think it might be possible IRL, but it's never been done. This is probably due to the A380 and the 747-8 being restricted from operating on IAH's "South complex" (runway 27/9).
https://dl.dropboxusercontent.com/u/23737560/KIAH_AIP_FSDT.zipShameless plug to demonstrate real world ops often have smaller aircraft on the longer 15L...
http://www.airliners.net/photo/United-Airlines/Boeing-737-924-ER/2470958/L/Doubles, baby!
Oh yeah, check out that traffic circumvention.
Little ones get to land in Austin....
Heavies arrive on 26L, or 27....