Generating a procedural planet/asteroid field

Lately I've been working with a game project where the player flies along a swarm of planetoids, placing bombs, collecting coins and dodging bad asteroids. As it would be quite dull to have a single hand-crafted map for the game, procedural content generation was required. The ultimate goal in map generation would be to create a path for the player to loosely follow. The path should have occasional obstacles but mostly it just contains lots of coins for extra score. Who wouldn't want to get a score as high as possible?

White is the main path, yellow is the obstacle option four. Read more later on.
So we need a path. And not just any path, a naturally looking path that shouldn't zigzag around too wildly. Rather, it should have small, smooth hops from one node to another. And to make the player stay on the path there should be obstacles. In theory there can be obstacles everywhere, just as long as they are not on the path. But note that complete coverage is not a necessity, as long as there is enough obstacles. There can be some open areas that function as alternative routes for the player. But how to create the path?