If things like battery life and range are important, there's really only a couple of things that one can do. Use the cheap FRS radios for short distance comms, most of them have decent battery life and most if not all can use some sort of rechargeable battery. Alternatively, one can step up and get a Ham license and use some basic 2m or 440 band HT's. They'll get out further, can be used with repeaters and if needed, they can be used to communicate to other Hams in the event of an emergency, with obvious limitations,, ie, terrain and range. I'm not that familiar with GMRS except to know that there aren't a ton of repeaters for them and anecdotal evidence is that without a repeater, you're not gonna get much better use out of them than you will from FRS.

One could theoretically pick up some used business band radios and use them without the proper license but frankly, it's probably not worth the trouble given the lack of range. The only advantage would be battery life and you'd most likely have a pretty quiet frequency on which to transmit if you were out in the woods. Disadvantage is that you couldn't contact anyone other than someone also using the same frequency(s). They're also pretty expensive.

I'd look at what you plan on doing with the radios and make the decision to either get some cheap but decent FRS handhelds or splurge and get some 2m Ham HT's.

JohnE