You are on the right track imo..loose the remora (put it up on RC, I've had a few and they are junk). Drill...drill...drill for sure. Trade the light to R3. I have found lots of random flow to work the best in a FOWLR. Keep the rock away from the rear glass as it will allow better flow from behind. Have you thought about a closed loop? An mp10es if you can swing it or 2 koralia #2's with a big return should be the least amount you would want. +1 on having a bigger overflow than return or drill somewhere else for a 2nd. I run a large reactor full of nitrate rubble in the sump along with kalurpa ( macro algea) and filled 1/3 of it with live rubble and a pc light. I have about 125lbs of large live rock in the 90g display fowlr and a giant skimmer. I have several large ,happy,hungry fish and low nitrate,no algea issues. Just my 2 cents