I'm going on a business trip to Frankfurt somewhere around late November .. this is my 3rd Euro trip and definitely I'll be sticking around for a while after the business is over .. there are a lot of places in my bucket list that i still need to visit but my schedule is pretty tight .. i'll be spending 5 days in Frankfurt then i'm thinking about staying for a couple of more days in another German city maybe Berlin or Munich .. from there I'll be heading to my next stop .. now I'm a bit confused since there are too many options .. Paris, Amsterdam, Barcelona, Zurich, and the list goes on .. what i know for sure is that there are enough room for only 4 more cities and i will spend no more than 2 nights in each city .. any recommendation u guys?