I avoid base layers and go slick. I don't want the extra cloth interfering with my draw or possibly being material to entangle a reholster. It's not cold enough here to need them. When I am cold, I add another layer or two on top of the tee or polo shirt. But nothing is 'tucked'.
When I practice drawing a lot my fingernails and even my fingertips abrade my riblets pretty good. I just say eff it and draw some more. I don't care about blights on my belly.