I never worried about the bottom no one looks through the bottom lol I do cut my rock so theres no points sitting on the glass though, dont want any pressure points. I'd still get a small piece of live rock (2-3lb.) to add some different live forms to the tank. If you cover the bottom with HDPE glue sand to it it will look like a sand bed
How tall is that lighting bracket? The hangers on those Tao's are about one foot long you could fold the cables and shorten them but it will hang at around 6in.
Most people create their own problems by not following the basics and refusing to stock appropriate to their system. Gregcoyote 2013
SPS = Stability Promotes Success