Fixed point numbers handle fractions just fine (it's kinda the point), what you probably want in this case is Q16 or 16.16. I'm not going to describe the whole process here cause wikipedia can explain better than me, but you basically scale the number: https://en.wikipedia.org/wiki/Fixed-point_arith...

The best way to avoid rounding errors is to just use fixed point (integers). If you don't require dynamic range then floating point numbers are the wrong tool for the job. Might seem like a pain at first, but it's well worth the effort to avoid all these corner-cases.

If you add CO2 as a gas, then hydrogen->methane->crude oil would be nicer (and more realistic ) path, if made expensive enough. https://en.wikipedia.org/wiki/Fischer%E2%80%93Tropsch_process Or could just assume CO2 is abundant and make the process really expensive, and produce a small amount of crud...

Turrets should have a reasonable warm-up time after placement before they can fire. They are a defensive tool and shouldn't be used offensively since it negates the need for many of the combat related technologies. This is especially true of laser turrets where you can place 20 turrets almost instan...