yes 7200rpm is fine,
In the case of most gamers' choice of games, we'd offer a dedicated gpu because the games are super hungry
But here.. league of legends only, an APU would do great but if a dedicated can be included without much sacrifice, great too, incase future graphics intense game were considered, but just for LOL... would rather get an i5 (we all want future proofing and this is a small step there) and leave the dedicated for later when need be
Also, i suggest you (OP) wait till September-Nov, X99(new 8core intel CPU) are coming out August29th, maybe prices may drop and allow you to do more with your budget