The tax and mining rates currently seen in PTS (assuming I've understood them correctly), make it virtually impossible for a single player to earn enough and the game will become unplayable. The mining units are difficult to operate, it took me many attempts to set one up just to get it to work, never mind the "calibration" minigame. Some of the error messages with the mining units weren't helpful. One example, I got an "unauthorised access" error message on a tile which I owned but the static construct was org owned. It turned out that I needed to tokenize the static construct before I could use the mining unit. Is there a tutorial on placing and using mining units? If not, it would be good to see one.
Please either reduce the tax rate or increase the ore mining rates. I've seen mention of having one "free" tile per planet, as per current rules, which I agree with.