Biggest winners in PvP after rebalance
I reckon:
Ludicolo: now that Razor Leaf is a damage powerhouse and it got Ice Beam to fire every now and then (still not very often though), it's finally useful in Great and Ultra.
Clefable: can't wait to get one and mash people to death in the Great League.
Jirachi: Confusion + Doom Desire is the shredder of almost everything now, I hope they launch the special research for it soon.
Munchlax (and legacy Snorlax): like Body Slam weren't good enough already.
Empoleon and Kyogre might finally see some use.
Ninetales (both versions) might be useful after all as well.
Muk's got a very useful and spammy punch.
And some honorable losers:
Minun, as Thunderbolt is not that awesome anymore.
Mawile and Loudred, as neither Astonish nor Bite was fixed, so it will stay mediocre.
Answers
All RL users are now worth a second look, that DPT is just busted. Ludicolo probably is very good now.
Clefable still has very low neutral TDO. MM makes it better, but I'm not sure if it's enough to make it good, will have to test.
Munchlax: Vigoroth is a straight up better user of Body Slam because it gets Counter. It was already a good starter, now it's probably amazing.
I don't think Bite needs to be "fixed". It's fine, even if it's far from the best fast move. EPT is more valuable than DPT, but high DPT has its uses.