From what i've seen, a few things:
The Apprentice looks super broken. Imagine Metaknight in brawl and that's what you have. Now i'm no SC expert, and i can hardly play the game so feel free to overwrite me but, his close range moves are super fast and his long range moves are quick as well, so he never has problems closing the gap. At long range his Force Lightning can chop off 30% of your gauge and mid range close to 40. His front grab alone does like 30% and his kick combos lead into lightsaber juggles so well that once they get goign it seems impossible to get momentum.
Astaroth seems nerfed--i find myself dying the same rate, he still is a tank, but it seems some of his quick moves got slower and powerful move lost power, possibly with good reason? i've always heard he was Top Tier.
as a Voldo/Raphael main, though...
Voldo seems much improved. Maybe i have a better grasp of him over the years but i seem to be doing real combo's that destroy and juggle my opponents with ease. Switching between his moonwalk/crabwalking stances just to pop out a killing blow back grab or some amazing voldo wheels has never been easier, and all of his poking moves have increased in power--good for when it gets down to the wire and a sliver of health is all you have to work with, has won be quite a few battles.
Cervantes still looks fucking great. And i still hate him.
Darth Vader looks like he needs more understanding--a lot of his force specials need to be done in succession to be good, just one does almost no damage and will throw someone down, while a chain of them pick them up, toss them around, up and down, and to hell and back. His front grab sucks so much ass it's insane, but his power makes you feel like you're fighting with batman when he wins.
Raphael is quicker, lighter, more fragile, more agile, and is a fucking vampire. Horizontal combos into bloodsucking fucking rocks.
Amy is also top tier. I don't have any real foundation for this other than an amazing range, and her ability to leave opponents in this sort of suction hole, where once you take the fight to her, there's no way you can escape--back dashes, sidesteps, she'll stun you at close range and fucking wolverine your ass. She's weak, but when you're hit 29 times in 15 seconds that doesn't quite matter.
mostly speculation but i feel it's more to the point of the thread!