High tier: Superman, Green Arrow, Solomon Grundy (anyone whose faced a pro grappler player will tell you they're dangerous!), Shazam (Raiden anyone?), Flash, Catwoman and Raven
Low tier: Harley Quinn (love her but still looks underwhelming gameplay wise), Hawkgirl (excited for her but I need to see more gameplay since the Battle Arena mostly showcased her as a punching bag with few tricks), and Cyborg (looks easy to counter/spam character)
Injustice: Gods Among Us Most Wanted: Black Canary, Steel, Martian Manhunter, Captain Cold, Livewire, Circe, Zatanna, Star Sapphire, Grodd & Poison Ivy
Well just going from what I've seen so far Catwoman for me, her combo potential looks crazy. and the more i see of her the more excited I am for this game. She may very well turn out to be my main, which is a complete 180 from my initial reaction towards her.
As for worst or just who hasn't made much of an impression on me. Doomsday (bar his super) and Bane. Now i'll admit big guy characters aren't my thing but when compared to Grundy who actually looks like some imagination went into his moveset. Both seem rather bland by comparison.
Joker has also been disappointing, I get there trying to go with Nolan version of him but its a shame to give such outlandish and unpredictable character such a generic fighting style.
I agree that Catwoman does look very good...reminds me of Sonia a bit to be honest.
Doomsday may not have the flashiest move set, but I think he looks pretty good. Imo he seems to have the best anti air moves of the characters so far, hes decently fast, and he can get in your face rather easily. Sounds like a recipe for success, or a nightmare if you are on the other end...kinda reminds me of Balrog a bit style wise. I can't wait to own with him.