<< Our system pretty deliberately is designed for two main parties. >>
No it is not.
What you call "our system" is the product of the two main parties conspiring over a hundred years ago to create and subsequently, before and ahead of every other consideration, maintain a cartel so insidiously and criminally all powerful that had it been formed between Ford and General Motors or between United and American all of its key players would have served out the rest of their natural lives in prison.
[Although, of course, once the mobbed-up corporatists who run the General and Ford and United and American et al cottoned on to and began to finance the political cartel it obliged them by making their criminal contortions "the law" -- and to Hell with our Declaration of Independence, Constitution, Bill of Rights -- and Rule of Law!]
Blessings -- Brian
BUMPping
That's about as clear as anyone has ever said it!