This is my Dark/Dark build till lvl23, not having played defender before im am unsure where to go after here with the dark powers although i played this build in beta halfway and it kicked [censored]

A few questions.
Is Tenebrous Tenticles worth sloting for damage? as i intend to be using the aoes as much as possible.
Does stealth stack with shadow fall and make you invisible to mobs?
Whats a good sloting for dark servant?
cheers
Exported from version 1.5B of CoH Planner
http://joechott.com/coh
Archetype: Corruptor
Primary Powers - Ranged : Dark Blast
Secondary Powers - Support : Dark Miasma
01 : Twilight Grasp acc(01) acc(5) hel(5) hel(11) hel(11)
01 : Dark Blast acc(01) acc(3)
02 : Gloom acc(02) acc(3) dam(7) dam(7) dam(9)
04 : Darkest Night endred(04) endred(19) endred(21)
06 : Tar Patch recred(06) recred(17) recred(21)
08 : Tenebrous Tentacles acc(08) acc(9)
10 : Combat Jumping endred(10)
12 : Night Fall acc(12) acc(13) dam(13) dam(15) dam(15) endred(17)
14 : Super Jump endred(14)
16 : Shadow Fall endred(16) endred(19)
18 : Swift runspd(18)
20 : Hurdle jmp(20)
22 : Stamina endrec(22) endrec(23) endrec(23)
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