Congratulations on your build and the courage to start a thread for input. Your stand and display in beautiful. Your evolve into a KISS format is key. As with most input I agree to flow in one direction. If you were able to put sox in two corners (current design) go for one side with a single bubble trap to control water level for sump and easier skimmer adjustment. Use 2/3 sump for sox, skimmer and peripheral pumps (UV, chiller, reactors ect.) then single bubble trap then 1/3 for return and probes (after the trap). I agree to no light in sump, much cleaner. If you want a refugium, you've already plumbed to garage where light will not be a problem. Iso tank has to be on stand alone system anyway. If you can, plan for SPS system parameters, you never know where this hobby will take you. Again, good job, I'm excited for you