Now, I haven't played Rakion in such a long, long time. But I guess I could give some tips on how I used to play.
I played until I was a level 20 Swordsman, and it turned out that Swordsman can be an extremely powerful class.
When you're at a low level, you can make swift kills, and deal heavy damage.
Combinations: A combination is a perfectly executed combination in which you perform special moves to either kill or hurt your opponent horribly.
My personal combination is...
Smack them with a sword, then grip, jump away, then special move them... (Right click)
You can kill them easy.
As for ranged swordsmans, it is recommended that you smack them around with a sword for a bit then you can fling as many daggers as possible.
I'm not finished with this guide yet, and it will soon be updated in the future.