people find enjoyment in a lot of playstyles - power gaming is one of them. That's why I think just having fixed number of stats you can adjust is the least tedious and most fair solution. .
The most fair solution is to have no option?
I play games SP only, and don't care one whit what others do in their games. What does fair even mean when an experience is entirely your own ?
But my general position would be to always allow players choice where it is practical and reasonable. Not doing so often reduces the appeal of a game and the reputation of the developer.