It's important to have a lot of Vulnerable damage, high roll on Heartseeker cast projectiles twice and a decent amount of Lucky Hit Chance (preferably 20%+) with glyph levels at 15. If at least these things are acquired, you can transition into this build and continue to find and temper better gear.

They both deal similar DPS. Bow will attack faster and thus more procs while Crossbow will hit harder. The amount of vulnerable damage you'd lose going to a Bow hardly matter once you've rolled/tempered Vulnerable damage everywhere else.

Bow is generally preferred in very high Pit pushes due to its attack speed, allowing more Undying and Umbrous procs which equates to more survivability. Outside of this, it is merely preference.

There is none in terms of damage. Both have implicit stats (critical strike damage for swords and close damage for daggers) that equate to less than 1% of your overall damage when you're geared out. What daggers are good for is making Shadow Step and Dash feel slightly more fluid due to the daggers having a slightly higher base attack speed.

Whichever 1 hand weapon rolls better is the one you go for.

Having 7 boards is nice, but there are some disadvantages with going 7 glyphs:

Those that will benefit from 7 boards are the ultra giga pit pushers looking to use devious for extra "splash" damage on bosses (Spirit caller or Malice) with minions. Those with average gear and not looking to push at a really high level will benefit more from the 6 board setup.

Elixir of Advantage II Stock up on this and/or craft a lot of these. The attack speed and lucky hit chance boost is godlike for this build. Elixir of Antivenin is also good and can be used along side Advantage II without overriding it. Both are extremely important for high Pit content.

Once you reach 1500% Vulnerable, Topazes start to become slightly better. While this is the case, the difference is negligible as the increase in damage is far too small to be recognizable (we're talking <1%).

No. The 6th skill can be whatever you want, as long as it has value. Some people take Death Trap for a pull, and some others take Flurry with Combo Points specialization for a boost of attack speed. Concealment is popular for elite hunting in very high Pit Tiers, while I personally like poison trap for easy additional CC and Retribution aspect procs (Wudijo likes poison trap for the defense in HC). These are all viable. You take what feels good for you.

Yes. Frigid Finesse is a good passive alternative.

A great basic starter amulet would be:
- Lucky Hit Chance
- Critical Strike Chance
- Attack Speed

This will get you by until you can upgrade.

Even without Dark Shroud on your skill bar, you can gain shrouds through the Umbrous Aspect. It is used in this build to profit from the enormous damage reduction especially when you get hit infrequently. You gain stacks by hitting enemies with Heartseeker (a Marksman skill) greatly benefitting from Lucky Hit Chance.

Cap 1

Cap 2

Read up more on Attack Speed in our dedicated guide by Ava.