These two links are pretty useful, one is a loottable spreadsheet, the other is a wall of text full of good info about prestige/proficiency:
Prestige/Proficiency Guide
Loot Spreadsheet
About Archers. Nyn gave good advice, as an Archer your dmg is going to come from inflicting Burning (dot) on mobs, then forcefully removing it with Piercing Shot (w/600% dmg talent). I personally think Aimed Shot is rather weak, its only saving grace is that it can proc the no cost buff for Rapid Fire. Since Aimed Shot is useful, I would try to get Amulets that buff its damage, with one of those Amulets also buffing Single Shot (basic attack, which does like +52% dmg to burning targets).
Stats are a mess, and keeping track of what you need is bothersome, but the simple path is going for Strength/Luck as your primary stats, then look for the secondary stats of:
Accuracy (increases your base damage)
Crushing Blow (chance at doubling base damage)
Crit Chance
Or you can go for Strength/Valor, and look for these secondary stats:
Accuracy
Crushing Blow
Temper (increases bonus dmg, and allows a chance at procing max bonus dmg regardless mob health; bonus dmg is related to a mobs health, the higher its health, the higher bonus dmg, the lower its health, the lower the bonus dmg, so Temper makes Bonus dmg useful the entire fight)
Don't use Jump Shot, since there is a chance you'll become rooted in place and have to dash to get moving again. Try not to use a charge up skill on mob that might move out of LoS, this will make you unable to attack until you switch elements or dash. If you "lock on" to a mob, your arrows will pass through any mobs between you without issue, but you're not locked on, your arrows will hit whatever passes in front of you.