As long as people keep it respectful/constructive (which most of it has been), I don’t see the harm in complaining. If anything, complaints can often lead to improvements.
Most of what I’ve seen complained about (pacing and animation being the top 2) are pretty fair.
Some are more subjective (Pronunciation of certain names and some minor character design changes) but those are usually presented as minor complaints, which is also fair.
I’ll go against the grain and say probably Mark. Given thousands, or tens of thousands, or hundreds of thousands of years, eventually something is likely to kill Eve completely and faster than she can activate her powers. She is by no means invulnerable (as seen by what happens to other Eve’s). A bullet to the head, a decapitation, an explosion, etc could all theoretically put her under.
She needs to be NEARLY dead in order to revive herself. Any quick, conclusive death would bypass that, and given enough time, I think that would likely happen eventually.
Mark, meanwhile, is likely to get even stronger over time. Not saying he couldn’t eventually bite it in combat or age (though we have no real way of knowing the Viltrumite lifespan since they seem to die ‘early’ in battle), just that I think Eve has tougher odds.