I agree with all of your points, except for the fact that there's no justification for him being so strong. Its the one place where his power level is justified. In a space comprised almost completely of dynamis, a character that is driven entirely by emotion is going to be as strong as he wants to be. Its dumb and boring, yes, but it isn't unjustified.
I much rather have had them drop a Boulder on his head while he was out doing something irrelevant, but im going to just keep
this as my personal headcanon
And I get that he's a literal personificationof endgame, but that really only works if we view endgame as a personal challenge instead of a way to spend time with friends... for me, that vibe is already covered by the power of friendship trope and the themes of perservering.