In my experience Starry Blennies generally will graze microalgae on the rocks and glass at first and gradually will take Nori from a clip and finally just about everything you feed the tank. They're one of my all-time favorite fishes with tremendous personality.
Keep an eye on your Tomini Tang though. I've had problems with bristletooth tangs harassing algae grazing blennies when they try to feed.
I can verify the fact that Starry Blennies and bristletooth tangs (in my case a Kole) don't get along. Nothing major but if the Kole catches the blenny grazing, there's a short chase.
As to diet, my Starry will eat anything I put in the tank!
Me three on the Blenny/Bristletooth issue.
I "had" a Algea Blenny and my Kole tangs persistant harrassment eventually led to his starvation. The Kole would aggressively chase the Blenny at every opportunity, IMO no, they should not be kept together.
I have had a starry since January, and added a small scopas tang about a month ago. Oddly enough, they are tank buddies and swim and eat together. We'll see if it lasts...