DET and its purpose of me being a SCH ?

I know it boost damage and heals but really by how much I'm currently re-working my BiS SCH right now

Animus

Daystar for all of my left side armor

DayStar Neck
HA Ears
HA Braclet
Judgment Ring Of Healing
Daystar ring

I Know all of these are BiS except the animus and the daystar neck
but I like the spell speed and the pie with it ....for endgame and 2.4 purposes how important is the DET I think I have a pretty good build maybe around 260-280 cant rememeber but should it be higher or is that fine for T6-T9 and future endeavors