Ok, i'm almost finished with her and it's neither bad nor good.
I can easily clear the whole cs without loosing much life (3% life leech does an extremely good job) and mana (4% on the same ring, awesome).
Still, this is in 1 player games and it takes some time...
I don't have my merc yet, but i doubt that i will do much more damage with it.
The most stupid thing is dia. He kills my decoy instantly and my Valk doesn't really work as a tank. It takes about 2 minutes to kill only him, and i need to run thru the whole cs to escape his wrath

If i get caught in his red lightning, i am fucked

I am not quite sure if it's gonna be any better with my merc, but I doubt that this build can kill fast/at all in an 8 player game...
Some experience that might help:
use a dual leech ring together with raven frost.
If you run out of mana, stop multi and strafe until your mana is full again.
On the way, multi like crazy and use mana pots instead of strafing to fill it up, otherwise it takes (me) longer to get to the cs than to clear it ~~
At the beginning of cs, use strafe like insane and pick up some mana pots.
In the main part of the cs, use multi like crazy. The load of monsters there will give you enough mana back.
For the bosses: cast decoy where they will spawn and multi the hell out of your bow.
Seis is tricky, i once hit the wrong button (caps lock instead of shift) and ran right into the mobs. Instant death.
If you're fieldof sight is clear, but you're not sure what's in front of you, spawn some strafe.
If a couple of monsters comes too close to you, don't worry. With dogde/evade you can tank 3-5 hits, depending on your charm. Multi like crazy to get rid of the enemies. That will also give you some life back.
For one or two monsters, always use strafe. Kills faster than multi when you have small amounts of mobs spread thruout the area. Also requires less mana.
For dia:
No idea. Fucking difficult for me to kill.
Kills your decoy, ignores your valk, chases you. Also, your arrows don't do much damage and you can't leech on him.
If you use guided arrow, it takes a while to take him down. If you use strafe, he will get you caught in his red lightning which is instant death.
Haven't tried with the merc yet, but since i don't really kill very fast, I guess he will get killed by IM before i reach dia, so he wont helpme with him either i guess

Altogether a fun build because you don't rely on your merc, but kills too slow imo, and does too less damage.
I do 5k guided, 3.5k multi and 3.7k strafe with exactly copying this guide...
BUT i need to admit that i didn't use all my skillpoints yet (bow skills are full, passives are not spent yet), and I have only 2 skillers sp far.
I will post again when i got my whole gear (including merc) and give some more feedback
