I'd go primitive or not, either way. I am always looking to get out somewhere, and meet new people. I'd be up for anywhere, but agree that Fourth of July in Colorado is almost impossible unless you ARE willing to go primitive, and hike in a few miles.
I went out to Guanella Pass to camp with 12 people this weekend. This is the place where I think we should have the camp out. It's centrally located. It has access to all types of vehicles including RVs and trailers. You can ride horses, mountain bikes, dirt bikes and quads. Theres a river you can canoe or kayak in or fish. Shooting is allowed. It is a very large valley that is completely flat surrounded by huge mountains. The woods on the edge of the valley provide excellent cover for tent campers. All pets are allowed. There is an abundance or fire wood. It's only 5 minutes from Mt. Evans Summit Trail. And did I mention it's free!. I will add pics to my profile page for anybody who is interested.