Hello! I don't have any more details for my experience with Leafeon, sadly. If you or anyone else feels that it deserves a different tier than B, then that's fine by me. It just felt like a solid but not perfect Pokémon when I used it.
Also, I really like how you started a new thread for US/UM! I won't be able to add anything more to it, but I hope the list can be completed one day. Keep up the good work!