Well, I'm not surprised in how things turned out. It wouldn't be Sasuga Kei without the push and pull of drama. I wonder if there are any Harem that can tell a story where the heroines get to be in happy relationships with people outside of the MC.
I feel like this hasn't been done before. The other girls are usually left single, moving on with their lives off-screen rather than getting explicitly paired up with secondary characters. They may appear for the rest of MC's shenanigans, but their own relationship isn't really explored.