Rather than picking the compulsory voting policy at the start and being unable to change it in game, it should be a cancellable in-game policy that goes unenforced, warning, small fine, heavy fine, etc.
Hm. I wonder if the there is a Neuron that could be manually modded to simulate this…
It would not be difficult to create a voting policy mod that amends such values so that you can change the percentage of the population that will vote. Just need the info to go away and do it.