Am I doing To Much (My route)

This kind of question is difficult to answer: ideally we want to avoid assuming that the way I travel is the way you should travel. If a person believes they will return to an area, they're more likely to spend more time in fewer places. But if they are not sure they will return to an area, there's an understandable interest in seeing as much as possible, however without turning it into a "death march to exhaustion" itinerary.To me, your itinerary doesn't look too exhausting--busy but not frantic. The only thought I have is: You might want to skip the Lucerne night and add it to the 3 Munich nights to get 4 in Munich: and this only because your 3 existing nights in Munich really only give you one full day in Munich, because you're using 1 day/night for Salzburg and 1 full day for a day trip to the Castles, which doesn't give you much time in Munich itself, whereas if you skip Lucerne and add that night to Munich the 4 nights in Munich give you about 2 full days to see Munich itself instead of one.

It sounds like not much Munich (3 nights minus a day @ castles and a day/night @ Salzburg). IMO Bruge, Amsterdam, Interlaaken or Nice could be a little less in exchange for more time in Munich. If you're doing museums, I would visit the Altes Pinokotek in Munich (or both Altes and Neues) over the Rijksmuseum in A'dam.

I'm not sure how long the train ride from Munich to Interlaken takes. Is it enough time to get some sleep? I haven't done overnight trains, so I can't give you good info on them.

Other than that, I think your trip is pretty well paced. All of the places you are visiting are good choices, I wouldn't eliminate any of them.

The middle part of your trip is too full. Don't expect to be too fresh upon arrival in Munich (the majority opinion seems to be that getting a good night of sleep on a train is wishful thinking). You won't see much of Munich if the three nights include side trips to Salzburg and the castles, and by the time you arrive in Interlaken from another night train, you WILL be exhausted.

I think we are going to X Salzburg - it was just a thought but doesn't look like the best option. Lucerne will most likely be X'd too - we want to go do outdoor stuff in Interlaken and just enjoy the mountains. Since we'll be living in Florence for 5 months we can always go back!

In answer to Brad's question above, I was surprised to see that the train trip from Munchen to Interlaken is over 7 hours...and it's not a direct route...you have to go through Stuttgart, Basel and Bern before you reach Interlaken.