[quote=Dervish]-snipples-
[/quote]

I think Stats can work, but in my experience - they usually work without any descriptions to go along with them, for the numbers. Dervish is right, the one above(in his post), is all over the map. 

I used stats in my Bleach RP, but didn't give them descriptions and just let the numbers speak for themselves.

For instance, if player A has 5 points in Defense and Player B has 3, then player A can survive more/take less damage from an attack than player B would if they were hit with the same attack, same strength, same circumstances.

I find it works better that way, rather than finding two extremes(Say, average human punch with no training/minimal street fights to say... punching a hole in a mountain). You have to start finding things that are consistent between them, so levels 5-6 don't take a small leap, while 2-3 take a huge leap).