After one day of effort, I am pleased with the progress I'm getting. Already, I have been able to significantly reduce the amount of time it takes to reload an existing level.
Also, in order to prevent all the problems associated with generation of terrain the first time you land on a planet, I am testing out the idea of having pre-generated terrain files. With this method, which seems to be working well so far, I will be generating a bunch of terrain files and including them in the game folders. These are generic terrains, and when you first land on a planet, the game will pick one of these terrains and use it to build the planet. All other features, like rocks, plants, trees, caves and other features are still processed at the time you land on the planet.
The benefit is that there is no trial and error going on while you're trying to play the game. You may have noticed that the loading bar jumps back quite often while the game generates a random terrain. Well this is all going to be taken care of now, so it will just load a prefabbed terrain, and start adding the terrain features. They are still being procedurally generated, but that's all going to be happening in advance now.
For me this is not as "cool" as generating new terrain configurations in real time, but the added stability and time saving effect of this approach make it far superior for the game.
In terms of how these terrains will appear in-game, it won't make any difference at all.
I hope to have these new features tested and uploaded by some time this weekend!