The Spinoff reminds us that it has been twenty years since the first MMP election. Like almost all of their commentators, I think that MMP has been a huge improvement to our democracy. Our votes count. Our Parliament looks like us. Our legislature is a check on executive extremism. None of these things were true under the old system, with its marginal electorates and male, pale and stale "representatives".
Things can still be improved, of course. I've consistently argued against the undemocratic 5% threshhold, which unjustifiably excludes some of us from political representation while limiting political competition. Using open lists or preferential voting for electorates wouldn't hurt either. Unlike others, I don't favour elimination of the "electorate lifeboat" because it improves rather than harms proportionality; if we're concerned about party game-playing and unfairness between electorates, we should lower the threshhold to 0.8% so that it ceases to be an issue.