Great game! I do have some suggestions though. . .
The obvious one would be being able to turn some of the structures. I can't optimize quite as well as I want without being able to turn at least the mergers and splitters. And sometimes the progression is a little annoying and forces me to tear down my whole factory because I'm not far enough in the tech tree to just buy more structures and set up a few more mana crystal lines.
Lastly, people have said this before, but to reduce clutter I would like to store buildings I'm not using. It could be a mid-game research and just puts a counter next to the name of the building on the build tab that shows how many you have stored I think.