I don't think an independent Transylvania would have satisfied people living in Transylvania. IOTL, the Romanians in Transylvania voted for union with Romania, and the Allies merely recognized that. Instead of antagonzing just the Hungarians, now you have antagonized the Romanians as well. There was simply too much nationalism back then.
Switzerland makes a good ideal, but I don't think there are anything like the cantons in Transylvania. The Swiss had several centuries of common government that built a communal identity and develop strong cooperative institutions. That simply just can't be imposed at will.
I expect lots of civil unrest in Transylvania, and real radicalization of politics in Romania. By forcing Romania to give up Transylvania, France just lost an important member of the Little Entente and its position in Eastern Europe. Politics in Eastern Europe is even more unstable. Most likely, Hitler partitions Transylvania however he sees fit during WWII. It's even possible that either Romania or Hungary try to seize all of Transylvania in an Anschluss style coup de main and become willing allies to Hitler if he gives them permission. Whether Stalin sees fit, after the war, to restore Transylvanian independence, partition the country between Hungary and Romania, or give one nation complete control is unknown.
Switzerland makes a good ideal, but I don't think there are anything like the cantons in Transylvania. The Swiss had several centuries of common government that built a communal identity and develop strong cooperative institutions. That simply just can't be imposed at will.
I expect lots of civil unrest in Transylvania, and real radicalization of politics in Romania. By forcing Romania to give up Transylvania, France just lost an important member of the Little Entente and its position in Eastern Europe. Politics in Eastern Europe is even more unstable. Most likely, Hitler partitions Transylvania however he sees fit during WWII. It's even possible that either Romania or Hungary try to seize all of Transylvania in an Anschluss style coup de main and become willing allies to Hitler if he gives them permission. Whether Stalin sees fit, after the war, to restore Transylvanian independence, partition the country between Hungary and Romania, or give one nation complete control is unknown.