What's killing my rendering performance? (pic included)

My performance is slow in my ingame level editor. I’ve worked hard to minimize draw calls (512, mostly in the UI). I have 1596 batched draw calls, though I wouldn’t think that’s a problem since they’re batched. Still, 1/3rd of my processing is spent on rendering, bringing me down to 30-60fps (I’m aiming for a baseline of 100).

I have 3 active cameras, one of them using Vignette and Bloom image effects. The other two only have a few UI layers rendered.

The level editor places everything dynamically so I can’t do static batching. Beyond that, is there anything obvious that you can think of, or see from the picture, that’s hurting my rendering? My computer’s generally capable of running Unity and most modern games at a decent quality and framerate.

Help huuuuugely appreciated. Thanks! (alt imgur link)

Figured out! See the comments above, @Fredex8 got my on track to the answer by looking at alpha of images. Lots of alpha and lots of sliced images in the UI was the problem.