You can’t fix a democracy back into being democratic. For example neither of the two parties would allow fixing the issues causing a two party system.

If you need some kind of revolution event to fix the smallest things, you’re better off doing it in one go.
The careful consideration can be expressed by not going too far from the most modern successful democracies.

Changes loosely are:

• multi-party system at all levels by never allowing winner takes all in any elections
• removal of lobyism in favor of tech-enabled transparency for high officials (livestream of every meeting, publicky viewable bank accounts, …)
• Severe nerfing of the president, potentially full demotion to a publicity role
• Additional checks and balances like a separate constitutional court for handling laws independent of the courts for people (i.e. break up the functions of the supreme court and move some power away from legislature)
  probably more I’m forgetting