That’s quite simple, Vaporeon as well Miltank were op, so they got nerfed in his hp.
Quite simple? I don't know about Miltank, but about Water-type pokes:
Vaporeon/C Vaporeon are very good pokemons, for sure. OP pokemon? I don't think so.
Nerfing 2.5k~ HP is too much.
Maybe leaving Vaporeon in 19k and C Vaporeon in 20k would be better.
Do you want to know which pokemons are OP?
Ludicolo, for instance. Has 2 Stuns + Healing + Own Tempo ability. It has 20k HP + 50% Synthesis = 30k HP.
I have seen how Ludicolo defeats almost 2 pokemons when duelling.
Gastrodon, for instance. We all know how OP it is. It has 18.5k HP + 50% Recover = 27.75k HP.
Vaporeon's Aqua Ring only heals 40%. C Vaporeon: 19k HP + 40% Aqua Ring = 26.6k.
I am pretty sure most players would say that Gastrodon and Ludicolo are MORE OP than Vaporeon, yet only Vaporeon gets its HP nerfed.
Please Rebalance team, double check Vaporeon or if you are going to nerf OP pokemons, then do something about Ludicolo/Gastrodon, for instance.
Thanks.