The best Archer in the entire series isn't technically an Archer, Wakka.

The Archers in Tactics can be useful once you get the hang of their weapon. However, you really need to know where to set them up or you'll end up making a lot of mistakes.

In XII, I like to give Penelo a Bow & make her one of my main Magic users, ala Rosa in IV.

Rosa is the only useful Archer in IV, everyone else who can use a Bow sucks @ it.

The Ranger's !RapidFire is one of the most useful abilities in the game.