If we can never have any choice other than a 2 party system of Republican and Democrat, maybe we could at least start having something like a mixed cabinet, so that the policies and mandates being created are more representative of different ideas on different issues instead of any single ideology.

I genuinely don’t mean to be snarky here, I promise. I’m sorry to say that you’re literally reinventing congress. The executive branch has become so bloated and overpowered that it sounds reasonable to hold elections for the Cabinet, because it is a group of people that write the policies of the US government. But that just further entrenches the Executive as the central source of power and policy.

The more appropriate and democratic (and more likely to succeed) response is to dramatically downsize the power of the presidency. The only reason Trump is able to do so much damage is because Congress gave the presidency in general most of that power and now specifically refuses to take it away from a senile criminal narcissist.

The executive has only grown so large because the parties constantly use the Presidency as a scapegoat and a sledgehammer when it should be a figurehead and a scalpel.