I don’t get a lot of PM’s about characters, but I have a friend with a sandboxed account so I get to play some of the guys I don’t have. Here’s where I find everyone. I have them in order of non-buffed, but they are truly interchangeable within that tier if they are.
TOP TIER–INTERCHANGABLE
1.)Iceman
2.) Hulkbuster
3.) Cyclops
4.) Jean Grey
5.) Red Hulk
MID-TIER
6.) X-Force Deadpool
7.) Carnage
8.) Thing
9.) Kingpin
10.) 4* Thor
11.) X-23
12.) Ghost Rider
13.) Professor X
LOW-TIER
14.) X-Force Wolverine
15.) Fury
16.) Ant-Man
17.) Totally Awesome Hulk
18.) Mr. Fantastic
Trash-Tier
19.) Sam Wilson Cap America
20.) Star-Lord
21.) Elektra
22.) Invisible Woman
23.) Devil Dinosaur
Disclaimer: This is my opinion and in no way should be used to do your own thang. This was more of a PvP view of characters with PvE being the tie-breaker.
Future: On paper assuming no changes, I see Miles and Venom pulling into the Mid-Tier, albeit low. The thing that saves both of them from low tier is Miles yellow and cheap skills, and venom for his yellow and hit points.
The one I see most controversy already is Ghost Rider. However, much like Punisher in 3* land he’s about in the middle of everyone, he’s a solid body, cheap skills and has the ability to one shot some people. He’s enough of a threat that you have to watch the other teams black as it could spell certain death for you if he gets 12.
TA Hulk just doesn’t quite make the grade, if his blue actually converted non blue tiles to blue charged tiles he might be worth the time, but his black skill is so hard to get off unless you are playing one of those goon boards or against Dr. Doom
Anyway that’s where I see it. If you are a newer player trying to figure out where to spend HP or invest ISO in you can’t go wrong with those first 13 characters.
Edit: After some comments I will add a 4th tier and clarify the others.
Top-Tier–Even when not buffed you still run them as they are an always character.
Mid-Tier–When buffed you consider them over the top tier and even run them over top tier. When not buffed you may play them but not at high level PvP but when buffed you would play them at high PvP.
Low-Tier–These are characters that need work, but you still play them over mid tier when buffed or in conjunction with a non-boosted top tier. However if boosted you probably wouldn’t run them in top PvP
Trash Tier–You never run them when boosted and these guys are in serious need of rework and balance