Last night I came up with something I think I'd do differently.
I think I wish my skimmer compartment on the left would leak slowly into my return compartment in the middle. Either by not applying silicone along the bottom of the center baffle, or by drilling a 1/4" hole in that baffle. The reason being that I could then do a larger water change without shutting off the return pump. Right now I can do about a 7 g water change from my return compartment before the pump intake starts sucking air, and I think if the skimmer section "leaked" into the return section it would allow the skimmer section water level to drop as I siphoned out water for a water change, and that way I could do a full 10g change (which is what I'm trying to do).
I don't think it would affect bubble trapping (especially if you do the no-silicone thing) because most of the water would still be forced through the bubble trap maze. Not sure how big a gap or hole you'd need though to allow the "leak" to keep up with your return pump, so that the water level would stay higher in the return section.
Nate