I know it's impossible to try out seats but, they do have differences that can can make even the best seat might not fit you well.
I have a Lepera Bare Bones solo and it's firm but, it's pretty good. I also have a Drag Specialties Predator and it's nice too. Both seats are a little more narrow than stock but, they provide better support for longer trips.
I haven't upgraded the shocks yet but, plan on it. Consult with the supplier (Like Progressive) what your needs are such as 2-up combined weight or just solo touring and your own weight etc. They should be able to come up with something that fits the bill.
If that doesn't work, you can always try out a big twin! lol.