I can't recommend anything from CM and that with a big IMHO.
I would say either a H7 or a small step up to thermalright macho or ninja mugen.
Air coolers are always a good investment because you get to keep them for years and the better ones will come up with free socket upgrade plates if intel/amd introduce new sockets in the future, so no need to cheap out. they usually hold their value better than even cpu's themselves.