Have been living and working in London, Paris, Zurich and Berlin.
Some thoughts on this:
None of the DAX30 companies has its headquarters in Berlin. Compare to CAC40 or FTSE100. Industry could neither survive 45 years of Communism in the East nor the difficult setting in Berlin West during the cold war. There was a transfer of subsidies from West Germany to West Berlin until 1990, preserving some of the industries, but subsidies were cut afterwards. Rebuilding industries will take 30 - 50 years.
After 1990 investors came to the East like gold diggers, prices for real estate moved up. A moderate version of irrational exuberance - not to be compared to Anglo-Saxonian type of real estate booms - and new rules for accelerated depreciation lead to considerable overinvestment. So real estate will probably stay cheap for a longer time.
What does this mean for a trader?
In Berlin a house with a garden close to the centre can be rented for a price that will get you a small 2-room-appartment in London.
Berlin is underpopulated. Green areas per inhabitant will be more than 100 times higher compared to Paris. Count on seeing lots of foxes and wild boar - actual population is not known, but 2400 were shot in 2008 within the boundaries of Berlin. Ideal, if you enjoy jogging, cycling or sailing.
Cultural offer is next to unlimited, more than anyone can take.
Safety: Better than any American city. There are some areas, where I would not feel comfortable to walk alone at 3 a.m., but there is no reason to walk around there....
Now to the shortcomings:
Berlin is not posh and shiny, its architecture cannot be compared to Paris or London, after World War II, part of the city has been rebuilt cheaply with a considerable lack of taste.
Berlin is not a shopper's paradise. Shops are less upmarket compared to other European cities, consequence of the lack of purchase power...
The beach (Baltic Sea) is a 3 hours drive by car, and although it is magnificient, it will be usually too cold to swim.
It will take you 1 hour by plane or at least 7 hours by car to get to a ski ressort.