That will work, the only flaws I see is are that you have light on only onside and if your return gets backed up you might have a pretty mess on your hands.
Here is an idea that will allow you to put a sump on your tank for cheap. Just go ahead and get yourself a small rubbermaid storage container and you can pipe in a sump with an ATO and some LR
Here is a picture of mine.....if you have the space it's not much more on investment.
Now getting back to the ATS...I have been running mine for about 2 years and I really like it. Yet, it adds to the hassle of maintenance. I've just recently been researching to get rid of my ATS and go with some mangroves growing in fiji mud. The mud replaces trace elements and as long as you mist the mangroves leaves with fresh water they work just like algae (ATS).
Let me know if you got any questions...I'm no pro just trying to help.