Stat wise there only two things I’d say are required. ACC 50 and GRT 20. I’ve seen some ACC 40 builds but I don’t find them that impressive. The rest of the points she can place however she likes, depending on her play style. I prioritize weapon penetration with mods/oils.
I would suggest getting used to horses, they are an archers greatest asset. Spec them for ACC otherwise they are hard to hit things on.
Here’s a few strats, your mileage may vary.
Knocking a mountless enemy with a full charged heavy or by running them over with your horse gives you free shots. I think pets>thralls for archers (especially mounted). If you knock an enemy a pet pounce attack can deal big damage and bleed them leaving them at a big disadvantage or dead. Sabers have the highest pounce damage but don’t bleed on basic attacks - jungleclaws do less pounce but do aoe bleeds on basics making them king for PvE/farming or fights against multiple opponents.
Mount vs mount - use scout saddles to outrun everyone you can, witchfire arrows cause bleed which can’t be cured while mounted. Use them to force dismounts.
Bow is the king of siege. Poison orb arrows/set arrows for thrall killing. There’s a bow that reduces gauntlet durability instead of using arrows to fire. Grass gloves + that bow + 1 explosive arrow to siege for cheap.
Creativity is your best friend with the bow. In one fight against a group built on an apex base I camped their elevators and used knockdown from heavy shots to send their reinforcements falling to their deaths while clan mates sieged from below. Smoke arrows, healing arrows, etc all can have uses if you can be clever.
My advice to her would be run from any fights she doesn’t choose. Stealth, range, and speed are her way to play. Best of luck out there, may her arrows always fly true! 