Some tuning on your printer will eliminate most of that roughness on the overhang.
You can turn/sand/etc to some extent to remove it, but keep in mind that prints aren't solid.. you only have a few walls of plastic before you expose the underlying structural fill.
I've not had time (and currently am down a couple printers thanks to shipping to/from worlds causing damage) to do much on tops but it's certainly a good application for printers. In theory, given enough print time, you could make very light weight, very large tops. The problem is finding 20+ hours to have a printer occupied and running smoothly.
Kyle