We are planning to drive from Munich to Strasburg with a stop at the Neuschwanstien and Fussion. Does anyone have suggestions for planning our time? We are wondering if we should stay overnight in Oberammergau (or another town) and then drive the next day to Strasburg or do this in one day?
You could to all of this in one day, although you would probably arrive in Strasbourg late. I normally don't think reserving tickets for Neuschwanstein is usually necessary, but this might be an occassion where it would be a good idea.
Oberammergau is in the opposite direction. No point in staying here to break up the trip.
If you wanted to take a very long, but very scenic route to get to Strasbourg, you could consider spending the night somewhere on the Bodensee (like Lindau, Friedrichshafen or Meersburg), then cutting through the Black Forest the next day.