Can you add a setting to turn off enemy expansion within a radius of the spawn point on each surface?
I had a player join a new team after many hours of play and the biters had expanded to the spawn and put him in a death loop.
I had to script expansion off, and destroy everything in a radius disabling achievements for everyone =(

2nd request. Only allow time based evolution per surface when players are on that surface. My planet is advanced, and the other starting planets have a very hard time starting out because of the high level biters.
I think I will just disable the time based for now.

As workaround, you can reset one time per surface the evolution via this:
/c game.forces["enemy"].set_evolution_factor(X, game.player.surface)
x between 0 and 1 for 0% to 100%.

For online server i would not advise to let time evolution happen, because its out of control for the offline player.

Yeah, I had to turn off expansion and time evolution, then reset the other planets.