I actually like the idea, but also understand Auria's concern (which are mostly caused by the harsh reality).
Advantage:
- Less loading time per overworld.
- More opportunities to make the overworlds more interesting (since the overworlds will be smaller, we have less performance restrictions).
- Easier to distribute the work among several artists (each can work on one overworld).
- Much easier to integrate high level addon tracks - they would just add a new overworld (which would still be a bit of additional work), though it would require us to have a 'hub' world that can be extended. Addons packages could be available as complete worlds to download.
Disadvantages:
- We don't have several artists to distribute the work to

- Overall more loading when switching between overworlds.
- Huge amount of work to redo the challenges, since they would need to be grouped and unlocked in a different order.
- Might be difficult to group tracks: often tracks that belong to one group have a very different difficulty (which we atm balance by unlocking them later). If we lock the overworlds and unlock them one at a time, the increase in difficulty might be less smooth (not sure that it is actually that smooth atm, but that's the idea we have at least
) - More drive-around time to get to the next challenge.
- Have I mentioned that we don't have enough artists? Oh yes, I have
More fleshed out suggestion:
We start with a hub world which is a kind of training ground (tutorial). From there some kind of portals, gates, doors, ... are available (mostly locked or invisible at the beginning) that will bring you to the various overworlds. By racing there you would accumulate points (same as what we have now), which will unlock more challenges (same as currently), but also unlocks more doors. We could enable a kind of quick-travel/short-cut mode to reduce the drive-around time: from the hub world you get access to a map showing the unlocked overworlds with their challenges. From there you could jump immediately to wherever you want to go. Also stk would save your last visited location, so if you go to story mode again, you might actually skip hub-world and directly go to your overworld. The various overworlds could contain additional challenges (I am thinking of Easter Eggs here

), which would make it more interesting to drive on them.
This would be something I would add when going from 0.9 to 1.0

But if anyone has a good idea how to get more artists ... let's start on it now

Cheers,
Joerg