Unless Larian can get Jim Cummings to voice Minsc, I'm not sure I would want to see him again in any form; it would be wrong somehow, as to me the voice defines this character more than anything else.
I don't really expect to play any origin character, because the idea doesn't appeal to me compared to moulding a blank slate character. But, I'm sure many people that prefer to play pre-defined characters would love to play Minsc. And if I were to play any origin character in BG3, Minsc would be preferable to the other existing companions.
I'm sure you could play Minsc any way you want, including evil, since the character in BG1/2 had suffered brain trauma and was rather unhinged. Obviously this would require some creative writing from Larian for Minsc to self-justify his actions, but would be perfectly possible.
