From what I've seen here in France, you'd have something like what Vladimir_M describes without bipartisanship. I prefer the French system with runoff elections, which means that "minor parties" have a real chance, because it brings bigger diversity of positions to public debates, which seems healthy for political and intellectual life (and it may make politics less polarized than in the US, though they are still quite polarized).

But despite those aspects, I don't think it changes much for the relationship between the bureaucracy and elected officials.