In England, a Majority of Citizens does not elect the Majority of Representatives.
First-past-the-post builds a direct relationship between a community and their MP. Residents come together to decide who most people want as their national representative. No one has more than one vote and it has to be cast responsibly.
All I will say is that there are particular features of the American constitutional system that renders a third party futile - at best.
There's no place for a third party in the United States.
In my view what you can't argue for is a system that is neither decisive nor proportional and can be indecisive and disproportionate at the same time.
I used to be a fan of proportional representation, but I am not at all now I have seen it in action.
Congress requires states to draw single-member districts.
If you went to a parliamentary system for America, you would have 30 political parties develop overnight—maybe 50.