Squirtle in PM2.5 is OP. He reminds me of Fox from Melee. Fast, quick powerful smash attacks, the ability to chase off the ledge and safely return (most of the time) and great with combos.
A couple things though:
Up smash is ridiculous. Way too powerful. I like being a **** with it, but it's got a ton of range and a ton of power. Needs to be nerfed a tad for the next version.
Side B chasing off the ledge is a high risk/high reward situation. If you can hit a recovering opponent with the side b off the ledge, you're pretty much guaranteed a kill. If you miss though, you're pretty much dead. Once again, high risk/high reward.
Love that he's just plain hard to hit due to his size. Even characters like Ike can miss him with huge moves just because he's tiny.
He looks like a baby. Legit.
Love the improved surf. Not only is it easier to recover, but it works as a pretty decent kill move when combo'd with tilts, aerials and smashes.
Also, I got a ****ING BLISTER on my right thumb from playing Squirtle. Hardcore.