Well, if they don\'t include character levels, then they probably need a system somehow similar to morrowind.
-use a skill X times to increase that skill. X will get higher when your skill increases.
-buy skills for X cash. X will get higher when your skill increases.
How fast X will rise, is an other point.
Usually, you will have a \"soft\" upper limit - you can allways raise your skill farther, but it takes AGES if you are allready extremely good in it.
I don\'t like that soft limit beeing to low.
As someone said:
Newbie firemage: yipee, i managed to ignite a torch!
Ancient powergamer firemage: so, what continent shall i turn to lava this afternoon?
With a limited PK system, it would be cool to be able to have a few ultra-power chars in game, chars who can fight 5 dragons with a toothpick, get kicked by their network while the fight, log-in again half an hour later to find their
char still alive...