I tried DSP, very fun game but the performance is terrible. i7-9700K and RTX2080 and I get 20 FPS before using even 1/10th of the first planet. Can't recommend it currently.
I've only played the demo of factorio, but on the same computer (AMD Ryzen 5, RX540) DSP runs much better for me - there's a noticeable slowdown on save now that I've covered about half my starting planet but other than that it's stutter free.
Interesting, while i haven't built a sphere yet I have factories going on multiple planets and haven't noticed any performance issues. I'm on a a 2700k with a 970GTX. Not suggesting you don't have issues, but perhaps there is a fix?