The mistake you're making is try to use human explanation and reasoning for how his monster powers should work. Their abilities don't work that way. It's supernatural, as stated by multiple characters.
You're right about that, but the MC still uses a human thinking brain.
Even if what you say is possible for a monster, it is not possible for an MC because the human mind is incapable of imagining such things. Giving someone a bigger bust is easy. You just imagine the growth of tissue and increase the fat reserves in the breasts. Changing someone from male to female is more difficult, but assuming you've seen them before, know how they work, and understand them physiologically, you can create fully functional female genitalia. But can you imagine something like changing neurons in the brain? It is unthinkable for the human brain. That's why I say that MC lacks mental capacity.
He also doesn't have to touch anyone "physically", If there's a mental link. He can access memories through it. We see this during his encounter with Sharon as they both looked through each other's memory without touching each other.
That is inaccurate.
The MC can connect to an existing mental link, but cannot create it.
And he can only do it if the telepath in question is much weaker than him.
Hell, Nyx legit can see dead people in the environment from their memories and yet you somehow believe the MC's power has to obey human logic.
Personally, I think that she can only read the echo in dead tissue.
Or she is just batshit crazy from corruption
And everything that was in the game so far could be logically explained and understood.
Although we cannot explain why some things happen, but when they happen, we know how they happen.
This is the main reason why people love this game and have long discussions like the two of us right now.
Weirdworld doesn't use the lazy
"it's happening because of magic!" explanation.
As far as "Pandora's box" being open, are you sure you've been playing the same game? You're a bit late for that line of thinking when we literally have characters blowing open dimensions, moving at "lightspeed", the MC getting dragged through links into one of those powerful monsters Domain, characters turning the sky dark and so on. Even with that made up hypothetical thing you created, the MC would still be at the bottom in this game. That's how high everything is already.
Anything that has to do with mind manipulation is
extremely dangerous.
Jake was only lvl 2 but he was still more dangerous than some lvl 5.
There are only a few hundred people with powers that are dangerous.
But there are countless people without powers who hold positions that make them at least as dangerous.
Giving the MC such an ability is a keg with gunpowder.
Then we could start asking the question:
"Why didn't he just take over the minister and the major world leaders to get them to give him all the military and financial support he needs?"
Like I said, this line of thinking is bad for the story.