I mean, it's not that I don't like the idea of these two as a couple, I just still stand that this kind of ending betrays the themes building up to this point. I've gone into detail on this on other threads, but I think that choosing one of the group to be a bride disregards the idea that they're five parts of one whole and the ideas of family that have been set up to this point.
Say what you will, if you like this ending, but I really can't find myself enjoying the last few arcs of this otherwise great manga because I feel it doesn't come together with the ideas and concepts presented earlier and so just kinda feels...empty.