Pick your favorite! Feel free to tell us why as well.
My personal favorite is Dwilight for a number of reasons. First, enforced SMA rules means no silly names and no idiots claiming that nobles and peasants are equals, or other such nonsense. Second, the size of the island ensures that wars are somewhat localized. No realms marching from the far north to battle realms in the far south. It would be possible, but only in very rare occasions, and not on a whim. Third, there are still lots of opportunities for new realms to be founded.