Another possibility that came to mind is that each level/game/whatever they are a pioneer from semi-random culture X who needs to prepare the random island for habitation by their people. Their people have semi-random requirements Y, e.g. must be safe, must have water, must have hunting, must find cultural artefacts, must build a town hall, whatever. The player having varying terrain, goals and abilities would give a lot of potential variation.

The last exploration game I bought had no real point to it, and I paid a substantially higher price for it than your average game on said platform.

Where I'm going with this, is maybe you don't need a point. Some gamers consider a game with no point a breath of fresh air. After all, you aren't making a RPG where some point is generally expected...

Another possibility that came to mind is that each level/game/whatever they are a pioneer from semi-random culture X who needs to prepare the random island for habitation by their people. Their people have semi-random requirements Y, e.g. must be safe, must have water, must have hunting, must find cultural artefacts, must build a town hall, whatever. The player having varying terrain, goals and abilities would give a lot of potential variation.

That's a pretty neat idea. It's almost like playing as the Settler piece in Civ :)

A further idea: The next time you play, you can play on the same island but hundreds of years later, now with the ruins of the culture from the last time you played. (Or even swap islands with your friends, and poke around in their ruins.)