My wife and I will be in Europe from August 12 until September 3rd. We begin our trip in Paris and end in Amsterdam. Now we just need to decide where to go in between. We did two weeks last years as well and found the 4 cities in two weeks was a great pace for us. We're young (27 and 24) and have plenty of energy to see a lot in little time. We were considering Paris-Prague-Belgium-Amsterdam or possibly Paris-Belgium-Berlin-Amsterdam. I'm open to any and all suggestions though.
*In our last trip, we visited Amsterdam (going back because we loved it), Munich, Venice, and Rome, so aside from AMS, those won't be visited again this time around