Codes 1128 300 301 302 303 304 on 2000 accent

Concentrate on code 1128, which is basically telling you the engine has been running too lean for a while now, so that explains the misfire codes, which is the rest of them. The main causes of those symptoms is usually a vacuum leak, plugged fuel filter (which you've already changed) exhaust leak, Canister purge system malfunction, or a weak fuel pump. By sounds of yours I'd concentrate on vacuum leak & canister purge system. If you have access to a fuel pressure gauge, check fuel pressure just to be sure, but I'm thinking canister purge circuit.