I converted your .doc
into a .jpg
Only change I would make is the configuration of your baffles. First one should be up in order to make a bubble trap. Second should be down closest to the return pump. That second baffle will be what determines the running water level. As water evaporates it will get to the light blue line and will need to be filled until it gets to the dark blue line. Don't go past the dark blue line as it will raise the water level in your skimmer area... something you don't want to do.
If you plumb in a line from the main pump you can run the fuge area with a ball valve to control the flow. This way, you won't need to run a second pump. Depending on what you keep in your fuge you may want more or less water flow and a simple valve will help.
Don't forget to add in a check valve to your return pump line to stop any additional water flowing back into your sump if the pump is turned off. Otherwise you risk flooding your sump when power goes off depending on how high you keep your return heads in your display tank. If they are an inch from the water surface, for example, that inch of water from the whole display tank will flow backwards into the sump until the line sucks air breaking the syphon. A check valve will avoid this... but keep in mind, they *can* fail... but are still recommended.