The Grand Melee!
Many asteroids with many enemies that attack right away.
Trees are cheap to make, have high points, grow fast, but they are limited in numbers.
Defensive trees have been hugely upgraded in strength. Do not underestimate them.
I have also included in the .level file all available options from the debugging menu that I could find. So, feel free to start doing your own tweaking and posting your own levels. (For those that don't know, just open the .level file with a text editor and start tweaking. Save your level, then load up Dyson and get seeding.)
This board is as close to a random map generator that I could make.
I hope you all enjoy it.
-Jamis