I favor the end drilling, my tanks face end out, and having the plumbing right there does block viewing space but its there if it needs to be dealt with. Standpipes as Jeff pointed out needs some creative design, I like having ply under the tanks, not just edge support.
My sump is a 75gal rubbermaid with about 50 gals as I have it set up, raised off the bottom is a 20 gal clear tote from the dollar store with 40-50 lbs of live sand and aragonite gravel in it, it gets the water from the tanks, flows through many bottom holes into the sump, and have chaeto in it, the return pump is in an enclosed box I am going to redo, the sump is pretty simple and basic, does have a light over the chaeto, just a clamp on compact fluorescent . Have heaters in the sump too.
I like the all 20s, can take one off line and drain down to 10 gals for fry, and drip in water, Its like a ten gallon with more surface area.
