Gnome Fighter/Rogue
Multiclass to equal amounts to avoid xp penalty, using mighty longbows, and utilizing fighter feats to maximize archery (Weapon Focus, Specialization, Improved Critial) ability and survivability (Dodge, Mobility). The rogue skills would also help survivability (Tumble, Use Magic Device, Hide, Move Silently).
I'd play him as paranid and sickly, always complaining about the latest disease he's contracted (which for once isn't due to [size=-1]hypochondria!), also I'd max diplomacy and bluff even with the average charisma, 'cause he likes to talk his way out of situations whenever he can. I'd also give him some kind of nervous habit, probably checking his pulse constantly or touching his forehead.
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