BBQNEO, Solidkick gave you an excellent reference here. Just do not allow garnish to hang over the sides of the container. While garnish is not to be "judged" I personally feel it definitely adds to the attractiveness of the presentation when done neatly, correctly! (No, I would not judge on it, however!) PORK: You need larger slices, arrange it neatly (don't just toss it in), and I think sauce gives a better appearance (personal opinion).
CHICKEN: Looks like it has been dipped in bread crumbs and I would have no desire to eat it whatsoever. Need thigh size to enable you to arrange three pieces in a row, two rows; total 6.
RIBS: REPEAT...you must have clean, smoothe cut slices. Assure it is not overcooked, of course. Get rid of that "ripped apart look". Arrange the bottom side of the ribs on the bottom of container and arrange neatly in a row.
BRISKET: Slice pencil thick and have clean cut looking slices. (This looks like a train wreck). Arrange attractively, use your choice of spritz to help make them shine.
IMO I really think all of your meats would be more attractive if you brushed on some sauce, too. Somehow, this just really makes it stand out. I think you have a lot of great feedback here and I wish you the best when you compete!!!!! Keep us posted. This is all constructive criticism in hopes it helps you become a winner!