A carry weapon is a very personal thing; different guns suit the needs and constraints of different people.
This. We can all tell you what we carry and works for us (which I will after rambling here for a bit 8) ) but ultimately you are about to start a very, very long journey through various holsters and guns, as well as probably some clothing.
What influences carry choices for me largely depends on two things:
Length of my overshirt: As in, when I do't have an overshirt I'm not concealing. My build won't let me conceal even a 3.5 inch 1911 IWB without looking really funny. But with a nice long overshirt, such as a flat black Carharrt one I can kinda conceal a Beretta 92. And definitely my 3.5 inch 1911.
Length of the gun: Because it shouldn't show when I bend over, kneel down, get in cars, hop over small fences and whatnot, this is obviously largely dependent on my .... overshirt. 8)
Thickness of the gun: Thinner is indeed better. Again, closely elated to the pattering and looseness of my holster and .... overshirt.
See what happens here? For me, and this is really only for me .... my overshirt is the most critical piece of equipment to conceal. For you, it might very well be the holster. And if you find out you can pocket carry, it might very well be a certainstyle pants, belt, or depth of pockets.
Really what you have to do is try things. A lot. 8) Hope this helps in getting you thinking about what works for you. All that being said I carry a 3.5 inch Officer framed 1911 in an OWB slide holster underneath an overshirt. Been thinking about getting a 4.25 inch slide for it, though, because it's kinds snappy for extended shooting sessions.