Okay, um...

I still really want to join this RP but I have some things to say. Conflicts between heroes is fine, but I also don't think they should be there to the point that it's incredibly obstructive to the rest of the RP. Someone who fights the other characters every time they try to take down villains I honestly feel would be a bit of a pain. I don't see why a character couldn't have a less extreme version of this. I would honestly get tired if every time I had my character fighting a villain another hero showed up to stop her. Especially when the villains are violent alien invaders or something like that. Maybe when they're more sympathetic or something, but, um... I don't even mind occasional fights breaking out but it shouldn't be a regular thing.

I also think overplanning is a bit of a danger, and making sure you have unique villain figures is fun but is also a lot of work, especially for a first-time GM. I do have a suggestion in mind to remedy this, but it's one of those things that would need to be carefully regulated in order to work since...

Sometimes people abuse being able to play villains and make kind of unfitting overly-dark characters.

But it can also make for dynamic villains that the GM doesn't have to play.

Perhaps you could make it so players MUST sign up as a hero before signing up as a villain?

... And I'll emphasize the HERO part, even if they're kind of antiheroic they shouldn't basically be a villain calling themselves a hero or something.