ThaLoraxIf I had to narrow that list down to 4 (personally), I'd go budapest, vienna, prague, and munich (instead of Berlin for geographical/travel reasons). Then any extra time in somewhere like Innsbruck.
This is a good list, but I might sub out Vienna or Budapest for Paris, as this is a lot of mid-eastern Europe and not a lot of western Europe. Plus, he's flying into Paris.
OP, I did a Europe trip last summer and went to all of the places you've listed, minus Budapest. Prague is a must do - food and drink are spectacular and hella cheap, and assuming you'll be going out, the nightlife is awesome. Plus, the city is arguably the best preserved large city in Europe, as it was the only major city not destroyed by WWII.
Geneva is absolutely gorgeous. CERN and the UN are really cool too. Unfortunately, its super expensive. Everything there costs a ton. We actually ended up modifying our plan and only staying there two nights because we just couldn't afford more. If you were adamant about seeing Switzerland, I would take an early morning train into Geneva from somewhere, spend the day there, take another train up to Zermatt (the Swiss side of the Matterhorn), stay the night at the hostel and hike the next day, then take trains to your next destination. Warning: you won't want to leave Zermatt. Interlaaken is another great choice for outdoor activities.
Munich was fun, a lot of history there. Great museums (especially the Munich museum and the science museum), and the hostels have lots of other young people looking to kick it. Drink a radler, they're tasty there. Find out when Munich's birthday celebration is and be in town for that weekend. They have a big festival to celebrate with lieberkas and beer and outdoor fun stuff. The best part of being in Munich for me was taking the S-Bahn just out of town to visit the Dachau concentration camp. Talk about moving; I can't put that experience into words. You just have to go and see, touch, and feel.
Vienna was cool, but we didn't stay there long. I'd recommend getting bikes and riding around the city. It's a very nice, easy loop. If you need a recommendation for a good restaurant to get schnitzel, I'll pass on the one we went to. It was fucking awesome. If you go to Austria, you have to find and try Almdudler, their national drink. It's like a lightly carbonated, slightly sweetened iced tea. Really refreshing.
Amsterdam was beautiful, especially if you take the time to walk through the city. The way it's laid out is really cool and the canals are lovely. The red light district was off putting - I couldn't believe that the girls waving at me behind the glass would have sex with me if I wanted it. It was weird. All in all, though, don't go to Amsterdam unless you want to get stoned. If you buy edibles, go to a reputable shop to make sure you don't get bunk stuff. For a good, free view of the city, climb up to the top of the science museum.
Berlin was actually great, we had a ton of fun with the history and memorials. The Berlin Wall exhibit is cool, Checkpoint Charlie was okay, but the best museum was that showcasing the Nazi propaganda programs. It's set on the former site of the SS Headquarters. Really cool. The Holocaust memorial is breathtaking. Also, they show an outdoor movie right next to the Reichstag every night. You sit on these steps that lead down to a river walk and they project a film about Post WWII Berlin history onto the wall of a building across the river.
We did a lot of walking in Paris, as we staying in Montmartre but didn't want to pay for transit to the main attractions. If you want to go on top of one building in Paris, choose the Arc, because then you can see the Eiffel Tower. Plus, it's cheaper and you get a student discount. The Luxembourg Gardens were awesome, there's a cool WWI photo exhibit there. Highly recommended. We skipped going inside Notre Dame and the Louvre because we didn't want to pay to go in. The highlight of Paris for me was climbing out of our window on the top floor of our little hotel and finding that we had a small flat balcony with just enough room for our bedside table and two chairs. We ate picnic dinners every night.
I concur with all above that say spend more time in less places. A good gauge for your timing is to ask yourself "If I never get to come back here again, will I be satisfied with what I've seen and done?" I think three days per place is about just right to meet that goal. If you wanted to really go above and beyond that, you'd need more time.
Before I finish, I'd say skip Venice on this trip. Italy could be a trip on its own, plus I've heard mixed reviews about Venice. Save it, your time on this trip is most precious.
Let me know if you have any more questions!
OP: "If you suddenly skied off a huge fuckin cliff and you only had time to throw one last trick before you died, what would it be?"
Malcolm: "id probably just flail my self to death"