Here are a few things I find odd or that I think might improve it:
1) beltloops!
2) if those aren't sweat pants, they should be equipped with a fly, and the cuffs should hang loose. I'm not sure as the texture looks like it could be either slacks or sweats, but with that collared shirt and belt, slacks would fit the look better.
3) the shoes do look a bit odd
4) I don't know the scenario of the game, so unless times are pretty rough, don't add any dirt to his clothes; normally people keep very clean, and some have a phobia of dirt
Remember those old guys? They made epic renders, I think one of them was called DaVinci, and all they used was MS Paint. Sometimes it's just skill....