i believe that if you have around three times the other character's quickness, you will double-hit them each round of hits.  of course, this is rarely practical.

as for how a fighter can compete with mages... mages must worry about both hitpoints and manapoints, so both pers and intelligence are very critical at certain points in their development.  for a fighter, only hitpoints are of a concern, so only persistance is critical at the right points of development.  of course, fighters do need to put points in 4 categories, while mages only need three, yet i still prefer fighters.  the reason being... they can use vamping weapon, which vampirize hitpoints back to them for each hit, which is effectively offsetting a mage's benefits from two shields and harder hits.  also, it depends on how much strength a fighter has, and how much iq the mage has... but in some circumstances, the fighter can actually do more damage.

all that being said, if you are only concerned about battles in the arena with clones, you will run into problems.  as you level higher and higher, less and less characters will be found in the arena.  the game is designed mostly to be for battling monsters, with player vs player (pvp) battles, and arena battles in there mostly just for fun and for fame, even though they are less important in the overall aspect of the game.

--jason