Well, after having a quick think on concepts, outside of a(n) Water/Ocean deity since, well, every Pantheon needs one of those to help shape an actual world and stuff, here's what I've got. I feel obligated to put this forth before I start writing up a character sheet mostly because I'd like to see if it's viable and maybe get some tips on what exactly his domain and what not would actually be. Here goes.

Rather than a God who serves at his own whim, think a deity who serves only at the whim of every [i]other[/i] God and any mortal who could afford to "employ" him so to speak. As you can probably already tell, I'm not particularly good at putting my ideas into words, but a basic concept was, say, God X wants to mess with God Y without God Y knowing it was God X, so God X sends God Z, who's willing to do any task no matter how grand or small, righteous or heinous, innocent or wretched, etc. as long as his fee is paid (What the fee is, I've got no idea.), from scrubbing a kitchen sink to massacring a village, so on, so forth. Figured it'd be a fun way to get involved in Godly power struggles without necessarily vying for the [s]Iron[/s] Throne. 

If it's too broad of a purview or a bit game breaking to have a God who essentially does anything as long as he's paid, I get it. It's probably a dumb idea to begin with, but hey, nothing ventured, right?

If it is indeed a dumb idea I should've kept to myself, I guess I'll just stick to the good old guy dressed in seaweed trying to keep everyone away from his islands and dolphins.

[s]That took far too long to type. I shuold probably sleep.[/s]