Well, if you've been to Switzerland, that might militate against an Alpine vacation if you want a different experience.
If you want personal takes, here are a couple of mine: I have to say, I loved Berlin--even though I don't do nightlife, I just found the energy there infectious. And the museums there are world class, restaurants are varied and excellent, and the history is poignant and fascinating. Public transit within the city is also great. Nearby is Dresden, which is definitely worth a visit, The rebuilt cathedral and old town are beautiful, of course, but also a sobering reminder of the inevitable high cost of modern warfare on civilian populations. We really enjoyed the museums there, too. And nearby to that is Gorlitz, a charming Silesian town that is on the Polish border. Check out the renovated buildings now housing cafes and shops, and then nip across the bridge to the Polish side and see the same kinds of building, unrenovated, housing cigarette shops and exchange kiosks. Eastern Germany is one of the cheaper destinations in this part of Europe, so we ended up splurging on lodging, staying in nicer hotels compared to other Western European travel for the same price.
Copenhagen is not one of my favorite European cities--frankly, it was disappointing to me, except for Tivoli Gardens, which was a lot more beautiful and fun than I had expected. The pedestrianized main street is nothing special--filled with international chains, second rate street performers, and too many junkies begging for spare change. I have on my short list of "must do someday" ideas a cruise through the fjords, though. Others may have more detailed (and differing) takes on Scandinavia.