Balanced class question

[igorith]

I've messed up my main character several times, since he was my first, and now I really want to learn the game properly. What classes are there that are in-between a mage and a caveman, and stay relatively the same strength throught the duration of game play? I figure the mage is at one end of the spectrum, being weak at low level and strong at high level, and the caveman is strong at low level and weak at high level. What classes do you suggest that are great for a newer player and will remain about the same strength from levels 1-30ish?