I wouldn't go the 24" wheel route - my wife is just a smidge shorter than you and we tried a 24" years ago. Limited tire availability, smaller wheels aren't so hot off-road, & heavy frames (to handle the abuse of kids they don't build 'em light). She now has a Jamis MTB that is a 12" or 13" frame (I think). Back to your dilemma, have you given any thought to a cyclocross bike? One could do pretty much all that you want to do, plus, if you ever got the itch to do any longer road rides, the drop bars + some slicks would be a better road bike than your Quick.