Whatever the outcome, it is a sad picture when a country splits apart. On the emotional level, I am happy for Germany, reunited. I am happy that more countries join EU, even if there are some troubles and worries. I am happy for Switzerland which keeps its national unity even if its people speak different languages. It feels like a wedding or a long happy marriage. I am not so happy for Yugoslavia or Russia/Belarus/Ukraine, where most people spoke very similar languages, had similar history but they failed to stay together. Divorce is always a failure – even a civilized one (as long as we treat life long marriage as a positive thing).
When a country splits there are family, friend and business connections torn apart. Customs and visas may creep in, different laws, currencies, different holidays. There often a nasty stench of aggressive nationalism involved.
I think more personal and regional independence but more national (but not ethnically nationalist) unity is the step forward – not multiplying governments, boundaries, checkpoints, and bureaucracy.