I have finally purchased Unity Pro. Up until now Sol 0 has been built using the free version of Unity. With this upgrade it is going to be much easier to optimize the game. I was a bit apprehensive about spending the $1500, but already this upgrade has been worthwhile. Sol 0 has been selling well enough that I can afford the license and also still have enough for legal things like trademarking/forming a small LLC. I think it's important for you to know where your money has been going, and thus far I've reinvested pretty much everything into software, hardware (I've never had a graphics card before), and legal stuff.
Object pooling, static batching, profiling, and much more are now possible (as well as a few possible graphics improvements). My goal for Sol 0 has been to have the game support 200 colonists running at 60 fps on a good system. I can't promise I will get there, but I will try.
You may have noticed that the most recent update introduced a few bugs. The last update was a bit of a mess, but it laid the groundwork for a much more stable and playable game long term. I'm cleaning up the issues and I'm going to try to move to a faster release schedule to keep cleaning up bugs as they appear. I've been a bit distant from the forums lately, real life has been a bit crazy and I would rather focus my Sol 0 time on programming and bug fixing.
That's all for now, but I'm very excited for the next few releases.