CharacterBuild > Gameplay
I am here for telling Stories where the values fit the character and not the other way around.
I have a similar problem with my Sorcerer from the dragon bloodline. I gave my Blár body shape 2 and he looks like a wardrobe, but if he had been useless as a Sorcerer at the beginning of the game, I wouldn't have skilled him like a Sorcerer. So he had Strength -8 (to get better Values for Sorc-Attributes) and I increased it to 10 with a talent bonus to at least remove the deductions on attribute rolls.
I feel similarly about Minsc. He is a ranger who is built like a wardrobe, which makes him individual as a ranger. Give him the stats he needs to be the character he is. Also, Jaheira and Minsc are characters who have had multiple "level ups" several times in the narrative. Their character sheets in BG3 should reflect that as well.