Try this:
Get an AR-15, and an expect that to meet almost all your needs. Get an NEF Handi-rifle, scoped, in .308 for longer-range use. These are fantastically accurate at long range, and very inexpensive and break down for easy transport.
I'd think that if this didn't meet your needs (two rifles is kind of a pain in the a$$) get the PTR-91K. 16" .308. Great rifle, and lighter than the full-size. If you're worried about the bolt not locking back, put two tracer rounds in the bottom of each magazine. When you see a tracer, reload.
The only limitation with the PTR is that it really does not lend itself to optic mounting, and therefore you better have good eyes.