As big of a Unity 8 fan as I am, I don’t think adding Qt dependencies in the Ubuntu desktop should be an option. Otherwise, we would probably be using Dolphin right now, as Dolphin seems more compatible with Unity 7 than the current Nautilus (it works with both Global Menu and LIM) and I’ve seen it running under Unity 8 too with LIM (though Unity 8 is a Qt desktop). I thought what we are doing here is testing Unity 7 with the default apps in the Ubuntu default .iso and hunt for bugs / glitches.
All the Unity 8 apps are great, I might help Ubports after we make 18.04 Unity a good, non-broken LTS. Even now, I’m currently ultra part-time tester here.