When you look at historical film , archers can draw 5 seconds their bow... In cRPG , that's 0.5 secs ... 
Second problem , kiting is a pain and that's not really realistic
are you seriously invoking realism as the way to decide classes......lol
If you really want realism then these things would have to added for archers.....
1.If a fully armored knight gets shot with a longbow, hes dead or at least maimed so bad that he flies off his horse and bleeds out.
2. Archers could kite since they are faster than your stupid FULLY PLATE builds which weigh a ton and no one can run in.
3.Any archer with a light build can basicly only do blunt damage to plate since those arrows cant penetrate especially when fired from small bows.
And for infantry
1.When you get slashed in the brain you are dead no continuation....and in the arm means u just lost that arm and cant use a 2hander effectively or can only use your shield/1hander depending on the arm hit.
2.You could swing that greatmaul probably 4 or 5 times before needing a break.
3.You would run rediculously slow or not at all in anything above chainmail.
