It's not a bad idea to have individual players base stealing settings. It would require a complete reprogramming of that part of the game. I think WIS made a statement years ago that of all of the suggestions, there was almost no chance they would touch this one because of how complex it would be to do.
The way the HBD works now, team total SBs and the percentages are pretty close to MLB reality. HBD gets there a different way. Instead of realistic MLB individual stats, we get players who steal 60 out of 65 and others who steal 10 out of 25 and 0 out of 10.