Suzi, here's the current seat on my Vulcan. Not much to look at, but it's more comfortable to me than the stock seat was.
As you can see, I mostly just added foam to the original seat and had it re-upholstered. This time I wanted to create a completely different shape for the base and then just add about 2" of foam. I want more support under my thighs and on the sides of my butt to help distribute the load over a larger area, hopefully making it much more comfortable. I could just spread out the seat pan where it is, but I'm long legged and wanted to have the additional height so I'm sitting more like I would in a comfortable chair. I do a lot of riding, and I'm on this bike for several hours at a time a couple of days each week. I've put just over 24,000 miles on her since I bought her new 18 months ago.