Just a few more thoughts, but these are all MY PERSONAL PREFERENCE. I'm not saying anyone is wrong, and if you have a system that works for you, awesome. Guns are like books and booze, each man has his own tastes.
I'm not a fan of carrying my gun in a pouch or fanny pack. I'll admit, I don't have much experience with them, but from what I can tell, they all require a zipper or something. I don't like zippers. I find they jam too easily, the zipper pull breaks, and they just take too long to open if you need the tool RIGHT NOW. The other issue that I have with them, is that if my gun is in a fanny pack, then it is not in a holster, IWB at 3-4 o clock, which is where, for the past couple years, I've carried my gun, and practiced my drawstroke from. Yes, that is a training "issue" not an equipment "issue" and like I said, if you have a method that works, I'm in no position to tell you that its wrong, I'm just saying that it might not be what works for me. I know a guy who uses a gun carrier from HillPeopleGear, and that might be worth looking into.
TrailRunner, you said you like the idea of a single stack...
When I carry, I think in terms of what problems am I likely to encounter. If I'm hiking where there are mountain goats, I want to have a plan for mountain goats. Same goes for bears, dogs, cougars, and meth labs. If you're running in a field behind the police station, you probably don't need to worry about stumbling across a pot grow, but a feral dog may be a real danger. If all you're looking at is size and weight of the gun, then you really can't beat one of the NAA mini-revolvers, but you're giving up a lot in terms of performance. If the you only have a 9mm and a .45 and want to stay within one of those two calibers, then we need to know what problems you're anticipating before we start offering solutions. Wild animals? Stick with .45, maybe the XDS. If one anticipates multiple assailants, either a gang/methlab/potgrow/deliverance scenario, or a Pack of feral dogs, then perhaps looking into higher capacity, even if its not a single stack, could be a good idea. Something like the SR9, SR9C, M&PCompact, or Glock 26 may be worth looking into.
To everyone, sorry if I hijacked the thread and was excessively long winded, but I'm trying to put off studying for finals as much as possible...
Hope this helps,
Chris "the Kayak-Man" Johnson