One thing I dislike about city builders is that you eventually reach a point where the lack of a struggle reduces my engagement. In games like Tropico 5 and Banished, and even grand strategy games like Rome: Total War, once my town/empire is large and growing and prosperous, and the difficulty is decreased, I’m not as interested. Tropico ameliorates this by tending to have short missions instead of long campaigns, and Banished is helped by the fact that death is constantly stalking you, and even the biggest town can have a famine strike with little warning, but even so, having a lot of infrastructure built up definitely helps.
I recently starting playing Valhalla Hills, and so far, it has the opposite problem. You only spend a short time on each island, which means that as soon as your small settlement gets big enough, you’re onto the next one. There are two things that keep me from really enjoying it, though. First is that there’s no continuity between islands. Your dwarves even drop their tools, apparently, because they don’t take them with them. There’s no point doing better than necessary, because it won’t matter in the long run.
Secondly, what your actual objective is, usually to defeat a handful of monsters guarding the island and the portal to the next island, is completely out of proportion to the amount of work required to get there. I need to chop trees and turn them into planks and build stonemasons and armories to get the weapons so my eight guys can butcher them, but in the meantime they want bread and beer and fish and meat, and I need my hunter to get leather and it all just feels superfluous. Whenever I unlock a new building, I didn’t think, “Oh boy, a new toy!” I thought, “Oh crap, more shit to deal with.”
What I was thinking of was a city builder with that same sort of island progression, but with more continuity. I was thinking you’d play as Polynesian settlers, island-hopping across the Pacific. At each island you would arrive, build, thrive, and then when the time comes, send out settlers to a new island. But each time you go out, you’d be able to take the best of the old island with you, choosing the most skilled settlers, taking the best crops and livestock, sailing in the best ships, enjoying the advantages of everything that you developed before. Ideally there’d be a genetics system, so you could even try to set up a little eugenics program, leaving behind everyone you don’t want on the old island, taking the best with you.
I think it would prevent success fatigue from setting in, while still providing enough of an incentive to success that doing well on one island wouldn’t feel pointless. Plus, you could take your time before setting out an expedition, perhaps setting out explorers to find the best islands, so when you left would be up to you. I would want some sort of mechanic to eventually strongly encourage you to leave. Maybe if population density gets too high, you start having Malthusian disasters of disease and famine, or people just start getting overcrowded and violent. I wouldn’t want to force it. I’d just want things to get worse and harder to deal with over time until it’s a better idea to leave while you can, before you start to lose the benefits of your current island.