Creating a logic for calculating level of character Vs. level of another character is not to difficult. And there are multiple ways to do it.
You calculate total skill points and that is the level of a character.
Separately you can split your total points spent list.
Categories would be something like
Combat: defensive and offensive with 1/2 the total of combat related knowledge /total points used.
Magic: defencive, offencive, and craft with 1/2 the total from magic related knowledge/ total points used.
Craft: craft creation, and 1/2 the total from craft related knowledge skills/ total points used.
This is a mock up but calculations along these lines can be used to compare characters.
Also this can compare characters Vs. monsters or mobs.
Since I don\'t know the rules of the system I can\'t really give a realistic equation.