I’m just 2 hours into the game so I’m not aware if anything changes for her in the future, but as of the moment you get her, I can’t figure out what role she’s supposed to fill.
She looks like a support/dps hybrid with her grenade range passive (so grenades?), ability to get to high ground (so sniper? But Dux already fills that role) and CC (taunt, root etc) (so support? But she doesn’t get much HP so taunt feels a bit stupid)
She’s a bit of an all-rounder. I tend to use her as a secondary stealth character/grenadier. Her Tree Hugger ability combined with a well placed grenade can be devastating to groups of enemies, and she has decent range with her Ancient Pistol.
Thanks for your reply
So you just upgrade her original pistol?
I’m guessing an assault rifle of some sort would be better if you’re going for some long range damage?
All silent weapons need to upgraded fast. Just a hint. 
Yeah I guessed that haha
While you’re here, could you enlighten me about how to use a ladder in combat?
Mousewheel. You change the levels with mousewheel to get up, or down, or grenade up, or Mothwing Fly…alsways mousewheel, buddy.
Well I feel stupid now that I realize how the icon is haha
Thanks
No probs. I only knew, because I remembered a Gameplay vid where they changed the level and I figured out. I thought at the start, that ANY attack will trigger all enemies, so I never got it to attack silently mutiple times. 
Yes spec on a harder dificulty, will be werry expensiv whit med packs otherwise.
I gave her the State Switcher for long range and let her keep her silenced pistol, so she is general utility.
She can be a powerful stealth criter on later point. And at first hers root cost 1AP combine with grenade and have fun =)
Later in the game her role shifts completely, at least it did for me. Just hand her the highest crit damage weapon, give her the +50% crit perk from high ground and the +20% crit chance from high ground hat, and just go to town on your enemies (provided you have easy access to highground - the passive perks are mutually exclusive, sadly, but you can use Frog Legs to get there).
At least on Very Hard, pistols drop way too much in damage in the late game, especially against heavily armored enemies. So it’s only really worth giving her a pistol if you can make sure to take out a target on the spot without alerting new enemies. It’s just not worth bringing a gun to an AR fight.
Further down the line, absolutely! 
She is the only stalker has jump, twitch shot and +50% crit at height.
During ambush, she can reliably lay down 2 crit shots from above.
I found this is extremely useful in silent killing a 26-hp target.