if there's a center brace, that means the manufacturer is using sub-standard (thin) glass and relying on the brace for support.
You could remove the center brace and re-brace it elsewhere. For example, use two glass braces at the 1/3 locations of the tank. You'd have even more structural integrity and it wouldn't interfere with the lighting.
me, I'm becoming quite partial to cube tanks for their efficiency in glass costs and lighting costs.
Too bad they're not "standardized" by aquarium manufacturers.