The problem with solipsism in these kinds of questions of society is that solipsism makes a lot of descriptive claims (what things are) but very few normative claims (what should we do about it). So solipsists could pretty much form any kind of society.
If I were to take a stab at it, I would say that it would likely be very hedonistic, with very little organized power structure (why would I let you lead me if you don't even really exist?) with very slow technological advancement.
The other problem with solipsism and societies is that the birth rate would likely be very very low. Because if you think that the world ends after your death, what incentive do you have to pass on your genes or give back to the world?
I'm not sure if I answered your question exactly, but I hope it helps!