My two cents, as an Orc player:
Orcs aren't always about fighting, and war and pillaging.
That MAY be an Orc, and tends to be the most stereotypical type.
I won't repeat what other have said - namely that you CAN attack any other player; there will be consequences, large and small - it's up to you to mitigate your own risk. This is politics and diplomacy - you get to choose your opponents, not your opponents' allies. So choose carefully.
Now, back to Orcs. There's the pillaging kind, the mindless warriors.
But Orcs can be cunning, they can be cruel - they can be treacherous, and they can be opportunistic. Perhaps being a warrior player means not broadcasting your intentions as loudly, perhaps it means actually roleplaying an interaction with another player so that you get the experience. Being in Illyriad definitely means developing multiple styles of play.
I would say that attacks are not 'frowned' on in general. Only blind attacks, on unwilling AND unequal counterparts, are. You want the freedom to play the game your way; but your desire doesn't trump the desire of other players to play in peace, in their way.
I have never witnessed the Illyriad community stopping two mutually willing players who chose to fight each other.
I would bet that if you posted a request for a sparring partner here on the boards, you'd find one quickly.
I don't feel my player options are limited simply because I can't pick a fight with my neighbors on a whim. It challenges me, yes, but as I've started to work out
here (and apologies for blowing my own horn):
http://forum.illyriad.co.uk/lashka_topic2756.html
there can be more to being an Orc than just fighting...
Again, my two cents.