When I say weak, I don't mean useless. 2 or 3 people on me and I basically won't die, but I don't seem to be dealing a lot of damage either. At first I thought it was just me, so out of frustration I logged my VR2 sorc on Trueflame. Standing there outside a keep and a magicka nightblade stealthed behind me and began laying into me, before I had any shields up. My health wasn't moving so I didn't even bother with hardened ward. After a curse and a few frags she cloaked away and didn't come back. It made me realise it wasn't just me having DPS issues. I'm still pretty new to the NB scene (level 44 now), but he can easily solo a dolmen in Cyrodiil and kill those boss things (they have two orange squares beside their health bar) with pretty high damage output. Mark Target on players also seemed to make very little difference... should I be relying on a destro staff instead of dual daggers? I do watch Sypher and Deltias build videos from start to finish, and they look great, but I love to make builds on my own to see how things work and don't work. Advice is always helpful though!
My build kind of looks like this at the moment:
Bar1:
Swallow soul
Teleport Strike (Lotus Fan looked to be absolutely useless. Please let me know if I'm wrong)
Concealed weapon
Impale (Execute)
Shadowy Disguise (I realise cloak is more popular for the purge, but the 100% crit on next attack just seemed too good, especially when my damage is low)
Bar 2:
Rapid Regen
Healing Ward
Harness Magicka
Sap Essence
Mark Target
Pretty much use Soul Tether for both Ultimates.
For gear, I use 5pc Seducer, 4pc Magnus (shirt, breeches and two daggers). I was having serious mag regen issues so swapped spell damage jewellery for regen and went with the Atronach mundus stone.