I've done this several times. A lot of time what you can do is dictated by lot and/or zoning restrictions.
I live in town, in a very old section of town, in a home I built a couple of years ago. I designed the entire thing to be as big as possible for the lot, and around a BendPak 2 post lift. I'm 12'8" clear to the ceiling, which was the minimum for the lift.
I'd absolutely go at least that high to fit a 2 (or 4) post lift now or later on. Whatever you do, don't put a 7' door in-- go at least 8', preferably 10'. You can mask the clear-span height by not using trusses and doing a front and rear gable, so that the vast bulk of the space is clear to the ridgeline of the roof. 24' is not really deep enough for a bench (unless all of your vehicles are Speedster size or smaller). The loft is neat, but stairs eat floorspace like nothing else and rob your height.
It's true that a building is never big enough, but I'd contend that going three stalls wide, 26 ft deep, with 13 ft clear (up) afford the possibility of 6 vehicles, assuming you have 3 lifts. Parking 2 deep seems like a great idea, unless you actually do it-- then you're forever moving vehicles to get to the one you want.
I heated the floor in the last two I built, and it's fantastic-- but I also put A/C in the one I've got now. A/C is worth whatever it costs. Also, insulate the heck out of it. It makes going out there a pleasure.
Buy once, cry once.