We will be renting a car.

Thursday – Arrive Munich am. (Munich Hotel)
Friday – Munich am. Drive to Hohenschwangau (Hohenschwangau hotel)
Saturday – Advance ticket for first tour Neuschwansein castle. Drive to Zugspitze and go to top.
Continue on to Berchtesgaden (Berchtesgaden Hotel).
Sunday – Salzburg / Berchtesgaden (Berchtesgaden Hotel)
Monday – Salzburg / Berchtesgaden am. Afternoon Grossglockner Hochalpenstrasse. Not sure where to stay.
Heiligenblut, Zell Am See, Lienz or back to Salzburg?
Tuesday – Back to Munich (Munich Hotel)
Wednesday - depart

Suggestions. Changes. Thanks all.

This is a personal opinion of course:

I think there's too much driving and too many stops. I would edit out the last leg (Hochalpenstrasse) and spend that time in the lovely Berchtesgaden environs - Eagle's Nest, Königssee, etc. Maybe a tour of the Salzkammergut and scenic Hallstatt.

Agree with Tuck that you are trying to do too much and that the area around Berchtesgaden and Salzburg is beautiful and should be given more time to enjoy.

Save the Grossglockner, etc., for another time.

If you look at a map, the roads between Fussen and Garmish are full of interesting sights. Wiessekirche, Oberammergau, Linderhof, Ettal Monastary.

What time of the year are you traveling?

I think AisleSeat is thinking of Wieskirche.