History gives you many examples to look at. Compare devolution of the UK to the fall of the USSR or the government in Egypt. Iraq and Afghanistan had help from a foreign power who had the infrastructure and people to carry them.
Also in your story you had a form of mind control from the former leader, a bliss like feeling. People may miss that feeling and want it back without realising what that would mean.
I think you will have people keen to assert themselves in your new political system for very different reasons. Some will want to help change, others will want to ensure their own survival. The affluent will want to keep their positions and wealth.
Could be an interesting story to write in a group. Each author will want different outcomes for their planet, much like the politics.