Topsheet and sidewall chipping. Best solution is to round it as best you can with an abrasive surface (like a file), but dont go too deep, as this can break into the laminate layers (core, fiberglass, yadda yadda). If you dont need anything that drastic, go with sandpaper. Better yet, I've been using wet sandpaper (look for it at most hardware and auto body shops). Soak a sponge, wrap it in sandpaper (120 grit is good) and brush over the edge, smoothing it all nice. Make sure to cover the rest of your topsheet with masking tape to make sure you dont scrub the surface of the topsheet and ruin the gloss.
As for brakes, you're pretty much stuck with whatever construction the binding manufacturer deems is good. Some are better than others, in my experience at least (blew up a Rossi 12 that way landing switch, huuuuuuurt).