Re the Deathmarks, as @Roci says the most common use in 6th is to drop them out of a Scythe. If you use twin Despairteks, this is definitely the best way to get the placement and results you want. Result = Unit? What unit?.
The disadvantage with dropping them out of a scythe is that they may not turn up when you need them to.
I started in 5th when flyers were basically non existent, so I tend to veil my first unit of deathmarks. If I have 2 units then I put the second in a Scythe.
Recently I nearly always start the
DM on the board, with the veiltek. The advantages of this are:
a) I have a much better shot at getting First Blood (I tend to run troop light lists, so secondaries are very important to my strategy)
b) The opponent has to deal with a T1 alpha shooting strike, even if it is nightfight. This is highly disruptive for the opponent, which is fantastic.
c) If the
DM do what they are supposed to, I remove a key unit from the opponent in T1.
Disadvantage is a
DS mishap - however with careful placement and a little luck, you can minimise that. I don't lose the unit often (in fact, never) but I have had it shot to death a couple of times (the opponent gets to place and places them 25" away, smack in front of their lines where everything can shoot at them). In any event, I view the unit as a suicide unit so it really doesn't matter - the distraction value is well worth it - plus, if they are shooting at my Deathmarks, they aren't shooting at the wraiths/spyders/
AB.
I recently had a spectacular success - Kharn and 10 bezerkers were hiding behind
LOS blocking terrain, it was night fight. I started the
DM on the board, marked Kharn. Veiled, scattered 3 inches closer to the unit (phew...) ........ boom - Despairtek killed the Bezerkers and the
DM accounted for Kharn. That kind of disrupted the opponent plan
So, re the
DM, pick whichever strategy you like - both have risks but
DM are too awesome to leave out of a 2000 pt list
imo.
Re warriors I have to confess I don't like the blob. I'd rather have 2 groups of 10 with
GA support. Better flexibility cos I get to choose whether to devote 20 or 40 shots (in
RF range). Sometimes, 20 will do.
edit:forgot something!