I would switch the fuge and return sections, no need to overcomplicate things, keep it simple silly. More hose connections means more potential points of failuer.
As long as you determine the water level correctly it should be okay. The display should be full and overflowing into the sump, then with the pump off fill the sump all the way. Then turn on the pump. This will take some water from the sump and put it in the display and this will be how it flows all the time. Mark the water level in the pump section of the sump with the pump running and this will be your absolute max water level in the sump (ideally use an automatic top off).
I wouldn't use filter socks, or any mechanical filtration (at least if this is a reef tank). They clog, take food from filter feeders, and the debris can breakdown into nitrate and phosphate if not removed frequently enough.
You really only need the two walls between the skimmer section and the return section, the water should go down first and then up. I would ditch wall number one.
For wall number 2 I would not go all the way to the top of the sump. In a worse case scenario and somehow the flow between walls two and three was blocked you want a backup. Some people feel this should never matter, but if it doesn't matter than not having that bit of glass up there definitely won't hurt anything, but could hurt if it is there.