Archer vs. Melee
Archers can be highly effective in a party. Primarily because if you kill a melee enemy at range, you don't get injured. Secondarily, because you always get a full attack, unlike the melee type that has to spend one or more rounds moving into range of the enemy. The third reason archers are effective (often overlooked) is that there are so many ranged combat feats that you can spend all of your feats on archery; Unlike the melee fighter who can not spend all of his feats on a single weapon.
The two best base classes for an archer are pretty obvious: Fighter and Ranger. Fighter because of the feats. Ranger because you get a couple of archery feats, but more importantly you get lots of skill points and other special abilities to make your character interesting in the non-combat portion of the game.
I would pick between Fighter and Ranger (with archery feats) depending on whether you want your character to be combat-focused or a more well-rounded character. Either way, all feats would be spent on archery with a Longbow (mighty composite). All stat increases would go into dexterity (for accuracy).
There are various PRCs available, but as a level 6 character I wouldn't worry about PRCs. Just pick Fighter or Ranger and put all your levels in one class.
The Favored Enemy bonus can really add up for a Ranger, particularly if your GM favors a particular bad guy race (Humans, Orcs, Giants, Demons, etc.).
