What kind of character he will be in Larian's vision?
As for my opinion, depending on the narrative with the petrification he has suffered, I'd say:
While he was petrified, his arms were broken by vandals in Baldur's gate, it's canon (later returned and statue fixed, but who knows what kind of internal damage has been suffered in the process). It is one way to explain his loss of combat ability (becoming low-level). Although it would be probably more correct to surmise that he fixed that problem already, somehow (by finding someone who was able to Regenerate his torn out arms, considering it is Beloved Ranger we are speaking of).
Another issue to think of is his mental state:
Being petrified for some decades could lead to a total stasis-like state (although the 5e rules don't say that), or he could have been subjected to a worse, bitter fate of someone devoid of senses yet conscious.
That could lead to various side effects - Minsc wasn't very sane to start with, so anything could happen. It would not be too foolish to think he had some decades to think and grow up in many ways, except that his body lost all his accumulated combat experience, of course.
It can potentially lead to a very deep and interesting character if Larian would allow themselves to go high and reach long.
