sometimes things are clearest when u suffer. and vegeta's venting seems realistic and any flaws are easily overlooked with that last line...

hell maybe Kakarott was just afraid others would leave him first...

I like this oneshot

as a side note though, Goku had already said that going to the third level would use up a lot of energy in that world than it would in otherworld and there were some other reasons as well but overall u are correct about everthing you wrote