Epoxy resin will give you higher bond strength than poly, so I agree with your choice. Chopped strand mat, however, is held together with a binder that dissolves in poly resin, but not in epoxy. I think I read somewhere that they're now making a CSM that works with epoxy, but I've never seen it. Here's a good article on the subject:
http://www.westsystem.com/ss/chopped-strand-mat-epoxy/
With epoxy resin, I would use a light weight cloth, say 10 oz. to go over superficial damage. If the damage goes all the way through the laminate, you should grind it out and go back with a full thickness repair that tapers out on both sides so it's about 12 times as wide as the laminate is thick.
Dave