The current way of choosing MPs rewards those who can get a small group of people to attach a party label to them. Mediocrity and even misconduct go unpunished. Independence from the party whip is of little value. And the results are highly visible: a Parliament in which there are too many time-servers, too many party hacks and too great a disparity in talent between top and bottom.
Open primaries are part of the solution. If candidates had to win the support, as individuals, of thousands of local voters, it would increase the quality of MPs, hold them to account and ensure they were more independent.