If you do anything I'd move the rocks in and away from the glass to make it easier to scrub/scrape. That's a mistake I made lol.
If you can get it off the back glass it would be a good thing from the standpoint of waterflow, but 12" deep tanks don't leave much room. I think audifeesh is talking about making sure you have room to scrape the sides without banging into your scape.
Yeah, I was referring mainly to the sides. I have rocks up on the back but also powerheads blowing along the back side to keep things from settling where I can't clean them up.
It's very difficult for me to keep portions of my glass clean because of my rock placement. Too late now though - it'll have to wait until I transplant to a larger tank (40B or 120gal is next for me lol)
I just wanted to raise that concern before you're loaded with corals and other critters. You don't want to knock anything over or crush anyone by moving the rocks accidentally.
id say mover the far left piece on top of the 2 right next to it on the right. it would get the one off the side glass and add a 3rd layer that you may need for a piece of coral that requires more light.