ET's Info-Stew

I have come up with the following four flight plans which take into account airspace and terrain, while minimizing distance flown as much as practical. Here are the flights from shortest to longest (CO Airports not including APA; flight time assumes 5 minutes of operations at each airport, not including fuel stops, and no wind; flight time and distance does not include detours to avoid airspace or terrain):

North
Distance: 213 NM
Flight time: 3.0 hrs
CO Airports: 9
States: Wyoming
Route: APA -> FTG -> 18V -> 11V -> GXY -> CYS -> FNL -> LMO -> BDU -> EIK -> BJC -> APA

South
Distance: 359 NM
Flight time: 4.3 hrs
CO Airports: 9
States: None
Route: APA -> 5V4 -> A50 -> PUB -> 1V6 -> 4V1 -> 07V -> TAD -> COS -> 00V -> APA

Northeast
Distance: 364 NM
Flight time: 4.5 hrs
CO Airports: 10
States: Nebraska
Route: APA -> 7V5 -> AKO -> 5V6 -> 2V6 -> 2V5 -> 17V -> HEQ -> 7V8 -> CNP -> STK -> FMM -> APA

Southeast
Distance: 637 NM
Flight time: 7.3 hrs
CO Airports: 8
States: Kansas, Oklahoma, Texas, New Mexico
Route: APA -> LIC -> ITR -> 9V7 -> K08 -> EHA -> H70 -> CAO -> 17K -> 8V7 -> LAA -> 7V9 -> LHX -> APA

The Southeast route is, by far, the monster. Without any landings or stops this flight takes six hours, so I'm really looking more like 8-9 hours. I could eliminate 64 NM from the route, but in order to get in New Mexico and the two CO airports I dropped, I'd have to tack them on to other flights adding at 62 NM to one and over 100 NM to another. So the smart thing to do would be to rent the plane for two days, and if I have to stay the night somewhere at least I don't screw somebody else over.

Total distance: 1573 NM
Estimated time: 19.1 hrs
CO Airports: 36
States: WY, NE, KS, OK, TX, NM