Hi,
PlayMaker can not compile Fsm into scripts, it's not how it works, so unfortunatly, no you can't do that.
Yes, Indeed PlayMaker is battle Tested and the core engine dll is well optimized and you'll find that memory Leaks will happen inside your own logic or scripts
and yes, if you are very concerned about cpu power, you should not even use Unity, but directly write in the native code for your platform, so if you are on IOS, use Xcode for example, but as soon as you even start to use Unity or unreal or any framework, it will have a penalty, so you have to weight this against what you can afford for that project.
But for a space gamer, what would be the concern for CPU perfs? the game play is "simple", and what you will likely face is graphic performances issues, more than pur coding issues, and by several order of magnitude as well. use the wrong shader or an effect that is not optimized and it will kill performances straight away.
you can verify the impact of using PlayMaker with the two Unity Learning projects I ported 100% to PlayMaker:
https://github.com/jeanfabre/PlayMaker--UnityLearn--SpaceShooter_U5.5https://github.com/jeanfabre/PlayMaker--UnityLearn--2dPlatformerAnd with the currently worst platform for perfs, being webgl, the difference is between 1 to 3 FPS out of 60FPS. the memory footprint being 1Mb ( the size of the PlayMaker dll core engine).
If that's not acceptable, then yes, you should not use PlayMaker and code everything using c#, but even with that, you will be expected to be a senior programmer because even with c# you can create terribly bad performing games, so watch out in any case.
Bye,
Jean