> Is it impossible because the current system is codified in the constitution, or does it 'only' require an amendment. 1.) The constitution can be changed 2.)

> Is it impossible because the current system is codified in the constitution, or does it 'only' require an amendment. 1.) The constitution can be changed 2.) The thing the changes the constitution is an amendment. You're prescribing a lot of "this is how the US political system should work" without really (it seems) understanding it.