I have a few question about my gear and how I can improve my DPS

I can't post links yet so my toon name is Damagess on Elune

I was wondering if I am gearing wrong? I do normally get DI in our raids, I flask and I pre-pot and pot during hero. My rotation is I start with MFx5 to get angel up then use fiend and MSx2 MB then MS till MB is off CD. Then I start with my dots, use MB on every CD, and mind flay when there is nothing more important that needs cast. I use the MS/MB rotation when fiend is off CD and try to line every other angel up with it. Any advice you be great

I also got Rathrak, the Poisonous Mind with our kill of Madness this week and was wondering if it would be better to use it with Demonic Skull or use my staff till I get the OH from Ultraxion