Being evil is definitely not impossible, nor any more difficult than being good. Simplified all you can do in the game is kill, mine/melt and use supportive/healing magic. Killing/fighting is something inherently 'evil', though rarely seen as such in games because it is the standard thing to do. Mining, melting and in the future crafting would be neutral. And the supportive, especially the healing magic, would be inherently good because you are helping without harming.
Agreeing that the most extensive thing that can be done is fighting and killing you could say that the game favors evil characters over good ones.
Anyways to come back to my points, it is very possible to be evil and not get banned. As a matter of fact I can recall quite a few encounters as Tyrnal with Sezrenade, one of the Outlaws, where he was far from kind to me. He even invaded Akkaio with a fellow outlaw with the intention to find and kill Vaalnor members. All of it was roleplay and I think the player behind Sezrenade is a very fun guy, not evil at all. I have talked to him .. before, during and after the rp events and have nothing against him at all. So there are good evil roleplayers.