I got another roster spot to fill. From the last PVPs, I have two Doom and one She-Hulk cover. I am not sure which of these to add to my roster. I am not planning on actually playing either character outside events where they’d be needed, so I was wondering who you’d think would be needed more. Or maybe I should save a spot for the new Human Torch? 
Depends on where you are at right now in terms of a roster. I would personally save all 3* characters, no matter how lowsy, like Loki or Daredevil, as they could end up being an essential character for a PvE event.
If you can, get both She-Hulk and Doom. However, I would lean more towards She-Hulk seeing as she probably would not be in Cover Packs for a while, after the She-Hulk rewards rain falls down, like they do with all new characters.
As for 2* Torch, I wouldn’t really bother with him, unless you are in the 2* range.
Yeah, I’m still in the 2* phase. I am transitioning, actually, but the only 3* I got over 100 is Hulk. It gets harder and harder to get covers I need and thanks to the level upgrade, my PVP nodes have gotten much harder than they were, so I am not going to place well in the next events.
Anyways, I don’t have enough HP to get both, so I guess I’ll go with She-Hulk then…
it’d be better if you could post what your current roster is so we could really help, cause you might be able to keep both if you have some lower tier 2*'s
There isn’t any character I want to ditch in favor of either Doom or She-Hulk, so that’s not a question 
I really just wanted to get an opinion on which character would probably more useful in upcoming events and thus should be on my roster rather than the other one.
Well, She-Hulk is newer so she is much more likely to be required in upcoming Story events. I’d say keep her, but the ideal solution is always get more HP (buy; earn in Prologue/PvP tourneys/training/Story events, etc) and keep both.
I agree with Ryu. I know people hate to buy HP, but it’s worth it when you later receive a bunch of 3* covers. I don’t think you need to go crazy with a $20 purchase unless you’ve been discarding lots of 3* covers. If money is a big deal, you should stop shielding and collect HP until you have enough slots. You’ll get enough good covers and ISO becomes an issue. Remember that this is a marathon, not a sprint.