Yeah, if you want to do more serious 3D, it kinda gets hard without some specialized tools. I guess you could spend extra time sculpting details in Sculptris, then spending more time retopoing in XSI Mod tool to get a nice edgeflow, UV map and then finally texturing in Gimp.
It's amazing how the whole process has changed in the last few years. I remember the above being standard procedure a few years ago and how tedious some parts were - now you can make the base models in Sculptris, auto-retopo them with, say, 3D-Coat, automatically UV-unwrap them in Softimage and texture them with ZBrush. You end up pretty much with all fun and no chores.
Now if only someone would make an app that can read minds and do the modeling for you.