Another really interesting level, well done _again_!
It makes a huge difference when fighting the infected seedlings that they are weaker than your troops so yeah this level isn't quite as difficult as the others, but it was still a nice challenge figuring out the right balance between growth and defense. I also really liked the planet whose energy level kept creeping up seemingly without limit, that was a novel strategic element to have to deal with.
This is also a very pretty level to play with if you can build up enough seeds to invade the comet--once I managed that and exterminated the laser mines, the comet no longer generated seedlings, and I got some interesting patterns very much like reverse comet tails by sending hordes of seeds to and from the comet at particular times.
One thing I did notice is that the AI didn't use flowers and just left them on its trees. I must've missed the invitation for beta testers, but could you just put me on your permanent testing list?