If you are looking for gas engine - any of the rigs mentioned will work. GM is putting the 6.0L V8 in all 3/4 and 1T trucks and vans and 3/4T Burbs. (no more 8.1L) If you want a diesel then you will have to go with Ford as GM only puts the duramax in the 3/4 and 1T trucks - nothing else. That may change in 2009 or 10 when the new baby max comes out.
Vans and SUVs make equally good tow vehicles and people haulers. Large vans have the most rear seat room - however SUVs usually have seats that fold down to increase cargo capacity when needed - you usually have to remove the seats in a van. Are you also going to be looking at a larger trailer in the near future? If so than go with a bigger TV now so you will be ready for the future.
07 Chevy 2500HD 6.0L ,6 speed auto, 4x4, Blue Granite Metalic
05 Arctic Fox 22H