We awarded each a certain cost. We then gave a total budget to players. The higher the base, the slower PC's advance in levels. Weak PC's zoom up the levels. It all balances out in a systematic manner.
People can have powerful PC's - there's a penalty.
People cna play weak PC's and there's a bonus for that. I hope these basic ideas will help DM's design better rules. It should also help curve munchkinism. These ideas are inherent in some very superior systems like Champions.