Eurowinter itinerary help

So to preface, I'm very aware this is not the ideal time of year for a trip to many of these places but it's unfortunately the only time I have free to go...

I'm still very much in the planning stage so would love to hear any of the unmissable things you would recommend in different places, restaurants, day trips, museums, activities, etc. I would also love to hear people's thoughts on the order of the trip (the Spain/Portugal part can't change but would there be any point ending in Switzerland and starting in Vienna in terms of Jan vs Feb weather or not really?). Also love to know any places people think need more/less time.

I'll be leaving late December after Christmas and coming back mid February. I will also be travelling with a friend living in Madrid for the Portugal stint of the trip.

Lisbon (4 nights)

- Sintra day trip

Porto (2 nights)

Madrid (5 nights)

- Segovia and Avila day trip

- Toledo day trip

Barcelona (3 nights)

**Flight to Geneva

Bern (1 night)

Interlaken (4 nights)

- Grindelwald and Lauterbrunnen day trip

Lucerne (3 nights)

Zurich (1 night)

Innsbruck (2 nights)

Munich (3 nights)

Salzburg (3 nights)

Graz (2 nights)

Budapest (4 nights)

Vienna (5 nights)

- Bratislava day trip