Debating about purchasing Bavarian Card-help deciding which castles to visit; audio vs English tours

I think you must be referring to the Bavarian Palace Ticket (14-day version). As you seem to know, it's valid for Linderhof, but not Hohenschwangau. I've been to all three, Neuschwanstein, Hohenschwangau, and Linderhof). I think my ex-wife liked Hohenschwangau better than Neuschwanstein because it was an actual home and lived in.

Hohenschwangau is right there in Schwangau and easier to see in the same day than is Linderhof, but Linderhof is included with the Bavarian Palace Ticket and thus not an extra 34€. I really liked Linderhof because of the extensive grounds, even without the Grotto. I spent most of a day at Linderhof. At Hohenschwangau it's a timed tour, and then you are out.

In Munich, Nymphenburg is included with the Palace Ticket, and I think I liked it better than the Residenz. My impression of the Residenz was too many Rococo rooms and displays of china and silverwear. The Residenz became kind of redundant/boring. I was ready to leave long before we got to the end of the route (it was not a guided tour, but once we got in, there seemed to be no way to exit early.)

Thank you, Lee. I am going to go with the Bavarian Pass.

Honestly, our worst travel experience in over twenty years of European travel was wasting our money and time to visit Neuschwanstein. A huge disappointment.
On the other hand, we enjoyed Hohenschwangau and Lindau.

I've been to all four.
I liked Linderhoff more than Hohenschwangu.
The Residenz in Munich is much better than Hohenschwangu or N'Stein.
N'Stein doesn't have self guided audio tours. Both castles can only be visited as part of a guided tour at a fixed entry time.
You can get an audio in other languages, but Since the tour is given in English or German, why would you need an English audio guide, unless I am making a wrong assumption that you are English speakers.
https://www.hohenschwangau.de/en/tours-tickets/official-tickets-neuschwanstein-hohenschwangau

I'm not understanding your route. You're going to drive from Berchesgaden first to visit the Zugspitze ( starting either from eibsee or Garmish-Partenkirchen) on June 23. But if that day is clouded over, You are going to stay somewhere near in Garmisch-Partenkirchen? Or are you going to then drive to Fussen and stay there? Then the next morning on the 24th visit N'stein in the AM and then drive BACK to Garmisch or Eibsee in the afternoon to visit the Zugspitze?
have you taken into account the distance and the time it will take to drive? Sure it seems like a short distance, but time wise, it may be slower going than you think. Have you taken into account the time it will take to either take the cog wheel train or the Cable Car and then the Gletscherbahn cable car? I assume that if you get there in the afternoon, you will only have time to take the cable car and not the cogwheel train. when will you fit in Linderhoff?

Just some things to ponder. Enjoy your visit to any or all of these castles. We enjoyed all 4 of them (but not in two days)

Sorry, can't answer any questions from your options.
We bought the Combination N=Stein and Hohenschwangu ticket and saw both on the same day, but it took a full day to do both.
Buying the Bavarian card depends on whether you will visit other palaces such as Linderhof and the Residenz.

I decided to purchase the Bavarian card and to visit Nymphenburg Palace and the Residenz (or at least the theatre if time is tight) in Munich and Neuschwanstein. I booked the 9:55 audio tour because it was the earliest tour we could do, leaving the rest of the day free for other things. Yes, you still have to go with a "guide", the difference is whether information is imparted by the person or the audioguide. Reviews were mixed for both, so I just decided to go with the earliest tour. (the audio guide tour). We are not going to go to Hohenshwangu, I hope that we will be able to visit Linderhof, even if if means backtracking to get there.

I realize that some people found Neuschwanstein very disappointing, but I want to see it, and for 5 euros and half a day, I think I will enjoy the views, possibly a carriage ride if my granddaughter wants to do that, and possibly the walk down through the gorge. Has anyone walked down that way?

One thing I learned is that you do not need to have purchased the Bavarian card prior to making a reservation. I will purchase it when I get to Munich.

to either take the cog wheel train or the Cable Car
and then the Gletscherbahn cable car?

You make it sound like the options are either the "cog wheel train" or "the cable car and the Gletscherbahn".

In actuality, from the zugspitzbahn Bahnhof next to the regular station in Garmisch-Partenkirchen to Eibsee, the only option is the cog wheel train. You can either get to Eibsee by using the train or you can drive there and park, but at Eibsee you have the choice of going directly to the summit via the cable car or taking the train through the mountain to the Zugspitzplatt below the summit on the back side and taking the Gletscherbahn the rest of the way to the summit .

The train from Garmisch-Partenkirchen takes half an hour to Eibsee. I would assume if you are driving you would go to Eibsee to save that time from GaP. If you take the train and the Gletschbahn from Eibsee all the way to the summit, it probably takes 50 minutes plus. I'm guessing the cable car (I took it in 1988, but didn't time it) takes about 10 minutes, but it might run only every half hour. The train runs hourly, so regardless of which option you take, you had better count on it taking 3-4 hours from Berchtesgaden to the summit of Zugspitze.

Even when the weather is clear in GaP in the morning, it often clouds up on the summit in the afternoon, so, unless you leave awfully early from Berchtesgaden, you had better not expect to up the Zugspitze and see anything the same day.

I, too, have been to all four (Linderhof, Neuschwanstein, Hohenschwangau, and the Residenz) plus Nymphenburg. Of the five, the Residenz was my least favorite (actually, the only one of the five I would not bother to go back to).