From a pragmatist...
Assuming they all fit and feel comfortable to you (Glocks never did with me), iff'n it were me...
If you want/like a grip safety, XDSC9.
If it doesn't matter 'bout the grip safety, either M&PC or XDSC9.
If you don't want a grip safety, M&PC.
Unless you
REALLY need some particular option offered by the XDM line (like different backstraps to fit your hand), I'd pass on the M line...
although you will be passing up the
MATCH GRADE BARREL!
If you do decide XD, see if you can find an Essentials package so you don't get stuck with all the not quite ready for primetime accessories.
Since the above two are double stacks, and thus a little thick, if you want to go thinner at the expense of round count, I'd seriously consider the Ruger LC9.
My personal CC is an XDSC9 with Pearce Grip Extender added to fix the danglin' pinky. In winter, I often carry a SIG P229R in 357 SIG.
Picked up an LC9 a few months back-probably gonna work it into my CC rotation for warmer weather and times when a double stack is a bit hard to conceal.