I've got a Dark/TA and an Ice/Time, so I'm parsing the relevant pieces of each build.
If you fire Time Wall before Time Stop, you get a mag 4 hold. For this reason, you may want an acc IO instead of a proc in Time Wall.
I originally slotted Tenebrous Tentacles for damage but I changed it to 1 acc, 1 range and 4 procs (I may swap the range for a 5th proc).
I slotted Life Drain with 4 Theft of Essence and 2 Devastation, giving me both healing and damage.
Why no Superior Blaster's Wrath? I would put that in Abyssal Gaze instead of Thunderstrike.
I've got Time Shift, but I'm not in love with it. I slotted it for stun rather than -tohit, but it's very skippable.