Since we can't have any flyable Russian 4th gen (or even 3rd gen, really, except for MiG-23) aircraft, how about some AI models of advanced aircraft? My personal favorites would be any Flanker (Su-27SM, Su-30SM, Su-35S) or Fulcrum (MiG-29SM, MiG-29K, MiG-35) variants, but I'm open to other suggestions.