Having a niche in OU doesn't mean he needs to be in OU. Look at Reuniclus, Amoonguss or Slowbro.Fair point, shows what I know about uu, but I still feel like it has a nice niche in ou
Everytime i see a Keldeo team i end up thinking "man, if he had Greninja/Lele he would have destroyed me". It's so difficult to find a good matchup for him because a lot of meta mons just invalidates him on sight.