Did you like Kunming? I lived there for 5 years before moving to Beijing (basically for the money) and think it has everything you're looking for. The pay there is not particularly high and costs there, especially housing costs, are rising, but for everything else it is perfect, especially outdoors stuff -- some the best mountains (imo) in China, the Mekong River. It also has an excellent chilled out local culture, good music and art scene, and the expats are a ... special bunch. Totally different from Beijing.
To answer your specific questions ...
1. Teaching. Do you want to teach? That is pretty much all you can do in KM unless you're a talented performer. I know quite a few foreigners who make their livings as musicians/DJs. There are some NGOs based in Kunming but you'd have a better chance of winning the lottery than getting one of those jobs.
2. Housing should run you around 1000RMB/month, more or less. Back in 2005 I paid 400rmb a month for a 1 bedroom 1 bath but from what I understand this is now impossible.
3. Environment is lovely, blue skies, nice weather year round.
4. See above
5. Also see above ... loads of opportunities for rock climbing, hiking, rafting, biking. Kunming is perfect for people who love the outdoors.
6. I think Kunming is still hovering around 100-150rmb/hr for part time teaching work. Monthly salaries probably average at about 5000rmb/month or just under for full time teaching jobs. Going from Beijing to just about anywhere you're going to have to deal with lower salaries. Cost of living is lower there but, imo, salaries in Kunming have not kept up with inflation. I sent out a few resumes a few months ago thinking our family might move back (husband is a Yunnan native) but the idea of working for like 1/3rd of my Beijing salary was really depressing. So be prepared for that if you consider KM.
7. Kunming has Kunminghua, quite possibly the best dialect in China.
8. I think the girls are ok? I'm a girl myself so not the best judge of those things. My male friends never complained. They're much less sophisticated than Beijing girls though. Maybe that's a good thing?