Reuniclus up from C tier ==> B tier
Cloyster up from C tier == > B tier
Hippowdown up from B tier == > A tier
Gastrodon add to B tier
On Ninetales not being in S-tier:
Sun is fantastic, Ninetales is not. Unlike the other weather starters, Ninetales doesn't really contribute to the team at all. It's actually a huge liability, since it's susceptible to Dugtrio, SR weak and has the offensive presence of Rattata. If Ninetales was a tiny bit better I could justify moving her up, but her mediocrity keeps her in A-tier imo (probably the reason why sun isn't everywhere too)
Terrakion in S-tier?
Gosh I don't know. Terrakion is ridiculously powerful and is one of the best offensive Genesect checks in the game (especially under Sand Storm). It's really, really, REALLY good, but is it really S-tier? You guys tell me!