Couple of thoughts
Paris - If you are going to the Louve spend a few more $ and get a guided tour, you see more (some places non-tour rabble do not see), well worth it (get them on-line, when you see the lines you will miss you will be happy). Paris Opera House is fabulous, also need to make reservation for a tour, really unique.
Amsterdam - take a Sandemans Walking Tour (free, give a tip, great way to see many cities in Europe) of the Red Light District, learn about the realities of the working "girls" and history of this area. As mentioned by NJHusky, Anne Frank House is a (real) must as are Van Gogh and Rijksmuseum and the Royal Palace (not as well known as palaces in other cities but one of the best). Great Indonesian Restaurant in the Red Light District, Aneka Resh, had the rijsttafel, maybe best meal in a restaurant anywhere anytime.
Berlin - the Holocaust Museum is excellent. The former East Berlin is much more charming than the former West Berlin, was surprised, have been there twice, nice place to visit as is very close by Potsdam, worth the day trip.
English spoken everywhere you mentioned, make triple sure you have credit cards with chips, otherwise it will not be accepted, don't get currency here, use ATM in Europe, check first but your bank will charge you $5.00 each time but you will get that day's actual exchange rate, get Euros here or there in a bank or Travelex you will pay more - lots more.