@ Solar Powered: Top 10 in Marvel is the following
Zero, Viper, Vergil, Magneto, Doom, Dante, Strider, Dormammu, Wolverine, Morrigan, Spencer, Nova
First 5 is pretty much set in stone at this point (not the order but the fact that these 5 are within top 5). I know I cheated by putting in 12 but these characters are the meta game right now.
Below them are Hawkeye, Taskmaster, Ammy, Wesker, Felicia, Phoenix, Frank, Akuma, MODOK, Strange, Deadpool, Joe, Storm, Haggar, Hulk, Thor, Sentinel (mostly viable due to Harddrive and Drones), RR, Spider Man, Firebrand, X23. These characters range from High tier to Upper Mid/Mid and are still legitimate threats.
Anything below these characters are too hurt by the meta to be winning consistently (She Hulk, IF etc get owned by zoning) or are better replaced by other characters filling similar roles (Iron Man). I legitimately think that Ghost Rider, IF, Hsien Ko and PW are bottom 4 with the last 2 being universally agreed as being 2 worst in the game.
Meta game revolves too much around missiles play shutting down most types of game plans AND TAC infinites while the rest of the characters kill you using unblockables or unreactable mix ups in order to 3 for 1 you. The anchors are essentially boiled down to 3 characters Vergil, Strider and Phoenix... any other anchor gets zoned out too well by the current meta. Skrull is exception, he can still make yolo comebacks but he is not a stable character. Vergil is the best of the 3 anchors because he kills you super fast and has a LVL1 hyper that allows him to get in with ease plus he can support the team with Spiral Swords and a solid Rapid Slash assist. Phoenix is a big liability but at 5 bars she is superior to Vergil because she can survive the incoming mix up and combo (which is a huge deal when your team is up against something like a Viper unblockable team or a Frank team because Vergil can't do shit against that on incoming). Strider also fills his niche among the anchors because he has a top tier assists while also being a strong anchor.
Basically the "go to" character shell in the game have become Doom for his Missiles, Beam, TAC infinites, safe DHC and the ability to stall games into frustrating opponent to mess up into easy mode TODs and Vergil for derp anchor play plus Spiral Swords DHC to guarantee TODs. What really changes is the point character and that is usually Magneto, Morrigan, Zero (soon to be). Viper is technically a top tier point character but she doesn't gel well with missiles, she instead uses Jam Session and Strider which is super potent. And she takes work to play with so people are just defaulting to X/Doom/Vergil. Dante/Strider is a similar shell to that where you have a top support character in Dante and an anchor but this set up takes a lot of skill to play and doesn't give you a ton of damage like those other 2 do.