[@Randomness]
Ok so I've gone through each of your sheets before so I could bring up the issues as of current as I see and as how I think Vita is interpretating them. But firstly please understand that using characters from other RP's is really not a "Good Idea" for this rp, and while it may fly in other rps you've been in, It is down to the GM's discretion if they are allowed.

Your first character was denied as a result of it simply falling completely outside of what the GM would allow for in-universe powers. Having a world hopping character simply didn't fit the concept of the roleplay, His entire concept was simple not a healthy thing for the continued life of the rp.

Your Second Character to put this simply, would be an obstrusion to rp flow, The point is allowing key RP interactions to occur as a result of magical methods, if you yourself are completely immune to such things in a sealed suit of armor, this forces the GM to have to work around your 'placed' obstruction. Things such as a widespread illusion do not work. What if a enemy wanted to play chess with you and it was through an illusion that the chessboard was playable. You yourself unaffected by illusion magic would be unable to participate, creating more problems then you solve.

Your Third Character was simply too simplified for the RP, As Isekai'd characters need to have a certain degree of power. If you had taken the GM's advice, you could of had some fun amping it up a little. But you moved on from that. You could of had cool energy blasters or an inbuilt reactor powering your almost 'super robot' level stuff. The issue with him was that he was too 'weak' for hero status.

Your Fourth Character infringed onto the boundaries of the overseers of the game (Due to his rule related abilities), but also nerfed himself to the point where he fell into the trap of the third character. He is simultanously too overpowered (if you remove the limits) and too weak (if you kept the limits as is), as his 'rules' can make or break an engagement.

Your Fifth Character, The Treehugger fellow. Would likely be denied for completely invalidating the reason for the games to occur, as he himself is able ot quite literally solve the 'infertile land for harvest' crisis by his mere existence, Which takes out one of the original hooks for the rp quite quickly. 

All of your characters had issues you could of addressed without fully changing your sheet! So If I was you, I would of taken the character closest to working (Three) and amp'd him up a bit.