Deeper generally just means more wasted space for the same volume. To compensate for the depth of my 50gal I grew frags for a little while in suspension. It was sort of a fun and unique thing to do for a while but it meant more maintenance because the fishing line would get quite slimy. It was also quite difficult to do anything in the tank with my hands as I kept bumping the hanging rods.
I now use a slightly shallower 140gal stock trough which cost about the same as a new 50gal glass tank but doesn't require nearly the same amount of cleaning and obviously provides a much larger square footage.
