[wild speculation]

Okay, so now we've got lots of individual elements and we can start tying them together. Family misfit, fetish for a non-elven culture, probably more interested in practicing with his sword than communing with nature...the guy's a natural outcast from elven society. Who are his parents? Are they on good terms? (Probably not...) Does he resent his brother's talent and intelligence and generally superior attitude? He certainly doesn't seem the type to play Caramon to his brother's Raistlin. That could translate to a general anti-intellectual bent, or just the 'brawn over brains' attitude you describe, hence the interest in orcish society. But he's spent so much time with this reactionary attitude, so much time delineating what he isn't--he isn't a stereotypical elf, he isn't a brainy guy, etc--that he's never really got around to figuring out what he is. Hence the aimlessness and lack of long-term goal. Potential character development could go in that direction. Maybe he realizes that this fetish with the orcs is just an expression of his internal frustration with elven society, and begins searching for some positive expression of himself. Maybe his fetish develops into a full-on mania and he devotes himself entirely to orcish ways. This is a Chaotic Chaotic Good character, because most of his defining traits are individualistic rather than moralistic. This is a rebel without a cause.

Or, perhaps his brother's taunting slides off him a little more. He wields the sword not as a rejection of elven society, but as an acknowledgment of what he is and what he does. At some point he said, "So I can't help people the way my brother can. Fine, I'll help them the way I can." His interest in orcish society is developed because in orcs he finds a people that better embodies his modus operandi. Maybe this causes a bit of a rift with the family, which is set in the traditional paths of elven doctrine and unwilling to consider the merits of another approach, particularly one espoused by orcs. Good Chaotic Good, an independent spirit who sets aside cultural norms in pursuit of self-improvement. Maybe not the somewhat mean guy you're thinking of, but there are ways and ways to make that happen.

[/wild speculation]

Don't have to borrow anything from what I say, of course. It wasn't exactly creative thinking on my part. It's an example brainstorm. But once such a character theme is developed, you have a better foundation for thinking about how to make your character's words and actions fit his motivations and personality.