Wolverine and Thor are both great tanks in team, but I don’t see them as dangerous opponents really. They are my last target when playing PvP (I target Widows and Storms first, since their theft or break the board and take the colors are quick to turn the tables)
I think the reason they see so much use isn’t that they are overpowered, but that they are perfectly balanced for what they do. I personally think that the reason we see less use of other characters is because other characters simply aren’t useful enough.
Cap A is one of the ones I look at in this. In theory he’s great. Defense, stun, damage; all with a return on your investment, and if you get them high enough, all with the ability to counter (replace) enemy tiles. Problem is, all his abilities have to be near lvl five to do this (I don’t know if Liberty yellow thingy can replace, mine’s not that high) and they cost too much to be worth it. Serious, standard Black Widow can stun better, for less cost. Terrible hat Magneto can replace enemy tiles for half the cost in gems, and Thor can hit twice (and collect yellow gems) before Cap A has thrown his shield once.
Same can be said about most of the characters collecting dust. The Hood’s attack ends his turn. Why? It’s not that great. Yellow heal with Spider-Man is stupid expensive, and only useful if he’s webbed the board up. I’m getting better out of Classic Black Widow for only eight or nine blue. Iron Man 40; man everything about 40 is just. You know what I mean.
In short, I think the problem isn’t the characters that people are using. I think a good look over the characters that aren’t being used is in order. If a power costs more than 12 of anything, it’s not worth the effort unless it kills everyone, or clears the entire board. If another character has a similar effect for cheaper, people are going to use the other character. It’s just the way it is.
Thor, Wolverine, Classic Black Widow, modern or classic Storm. You see these characters used quite often because they are all great at what they do. Thor right out kills folks. Wolverine does too, plus he helps the rest of your team do the same. Classic Black Widow heals up your team, and keeps your opponent from using their powers. Both Storms mess up the board, and collect colors doing it. All of them do their jobs.
Finally, most people might want to remember that your most useful character in attack is often your weakest link in defense. Classic Black Widow is mine. She’s the topping of my cake. She’s the reason I haven’t had to use a heal in PvP in forever, save for some bad luck, or cockyness on my part. I’m willing to bet though that she’s the first one killed when someone is attacking my team. Your best is not your best in defense.
And your Wolverine and your Thor are the least of my concerns when I face you. My opinion of course.