The creativity and novelty in this level leaves me in awe... completely brilliant! I could go on effusively but I want to point out a bug that can prevent victory or ensure defeat...
I've played three times so far, lost the first one crushingly, won the next but only after tediously working around the bug, and couldn't win the last due to it.
For some reason, this level seems especially prone to a rare bug I have seen a handful of times in the past on other levels, whereby an asteroid will have active trees belonging to an empire which is not the empire that owns the asteroid. I do not know what brings this condition about and I have so far been unable to witness it happen in the act; perhaps it happens when the defending empire plants a new tree on the roots of the tree being invaded just at the instant the asteroid is lost? In any event, after playing through this level three times now, each time I have ended up with several asteroids with this schizophrenic condition. The misplaced trees will spawn seedlings of the empire which owns the tree and not the one that owns the asteroid, and crucially, seedlings will not attack a friendly tree even if that tree is on an enemy asteroid. All this is essentially a curiosity, but the real problem comes when all three trees on an asteroid belong to an empire which does not own the asteroid.
The first time I saw this, it was my asteroid with enemy trees on it. The enemy infected AI sent his seedlings to conquer it, but finding no trees to attack, kept accumulating seedlings and soon had a huge force squatting there. This was late in the game when the enemy AI had only a few asteroids left, so due to your nefarious coding these were enemy super seedlings. The problem was that my friendly infected AI kept sending seedlings to the slaughter in defense of this asteroid, and would not attack any of the enemy's remaining asteroids to finish the game. Landing in a sea of over 1500 enemy super seedlings vaporized the friendlies instantly as they trickled in. I was eventually able to overcome this impasse by carefully placing my mine (fully upgraded) at the proper distance from the asteroid, and in the path of arriving enemy seedlings, so it could gradually zap down the enemy seedlings yet avoid being counterattacked. It took a while.
The second time I saw this, the condition was reversed--there were three friendly trees on an enemy asteroid. This was an unwinnable condition since my friendly AI kept sending seedlings to conquer the asteroid but was unable to since seedlings won't attack friendly trees.
My suspicion is that the underlying bug (trees that don't belong to the asteroid owner being able to exist) is something in Eufloria itself, but you are certainly better suited to judge that or know if there is anything in your code that makes it more likely.
Anyway like I said this is a truly great and innovative level that opens up new gameplay possibilities for Eufloria... well done yet again!