Roahin: The truth is that Zen Archer is the best archer class and through extension, Lann will be your best archer. The Zen Archer gets full BAB, Flurry of Blows as an upgrade over everyone else taking Rapid Shot, and it replaces your bow's innate damage for the monk's unarmed strike damage (scaling up to 2d10 per arrow before buffs). Here's a tip, Enlarge Person is usually bad for archers since it reduces their Dexterity and therefore their chance to hit. Lann uses his Wisdom to hit so there's almost no downside to casting it on him, especially since as of level 5 that'll make his bow (whether short or long) do 2d6 base damage.
Most people that resist the noob trap temptation to turn him into a caster discover Lann as one of their top damage dealers pretty early on. And he scales to remain at the top the whole game.
Abishia: Wenduag, auto build is really good also
she is auto build warrior with bow really top dps to be fair.
I personally go for this build for Wendu:
5 Levels Fighter
15 levels Slayer (Vanguard)
Feats/Slayer talents
Two Weapon Fighting
Improved Two Weapon Fighting, Outflank
Weapon Focus (Throwing Axe)
Weapon Specialization (Throwing Axe)
Greater Two Weapon Fighting, Improved Critical (Throwing Axe)
Deadly Aim
Weapon Finesse, Slow Reactions
Accomplished Sneak Attacker, Crippling Strike
Critical Focus, Opportunist
Double Slice, Slippery Mind
Not saying it is best build or anything but just for "run her as autolevel up version" is far from what Lan can be in my opinnion. That Outflank for "everyone" is kind of nice touch and save other party members for taking that feat.