My nightblade is of the healer/warlock variety, using a resto staff of destro staff (whichever I'm feeling that day) to deal mostly single target at range, yet still remain capable of mopping up the one or two that may make it close to me. I've recently gotten Drain Power on my bar; haven't morphed it yet, but I'm likely going with Sap Essence for the heal. There are a few things that I'm fuzzy on, so I was hoping someone has some confirmations on some skills available to me:

1. An easy one (I think). The Sap Essence morph takes away the damage component of Drain Power. Correct me if I'm wrong, but it will not take away the weapon damage buff, yes?

2. I have been toying with Shadowy Disguise lately. The 70% critical strike chance will apply to Assassination skills, such as Strife, correct? I believe that it will, as the tool tip doesn't give me any reason to believe that it won't, but I'm not sure I'm seeing that in game. Any one 100% sure on this?

3. An extension from the question directly above: If the critical strike chance does apply, this will in turn increase the amount of healing received from Strife/Funnel Health, correct?

4. I'd like to give myself a little more AoE capability for funsies. (I don't want to discuss what class or build works best for AoE, just some class specifics.) So, let's talk about Teleport Strike, which I'd like to use to put me in range for Sap Essence and Elemental Blockade. I like the look of its morphs. Lotus Fan seems like a good start to the AoE action with the AoE bleed effect, however, can anyone confirm that Ambush will only affect the next amount of damage on the enemy that it hit or will it apply to the damage of any "next attack" of my choice? (Hope I'm being clear with this one.)

Any and all assistance will be greatly appreciated and probably get you a rate up.