Gerrymandering already exists. Voter suppression was huge in the past, and may become huge again. The supreme court made sure of that.

And also... the supreme court keeps issuing partisan decisions.

So... what is left? Number 3?

I guess you're arguing that federalism protects people, but how does it do that in a way that isn't already being eroded?

There's no voter suppression in US, and it won't stand in courts even if somebody pushes it. Supreme court keeps using partisan decision in favour of Dems and GOP, so it remains balanced. What's left is everything you mentioned.