I have only visited Berlin the once but went on a Fat Tyre Bike Tour with a very informative guide. Your plans sound great.
Just read about the Marathon Of The North were only 1 runner ran the correct distance due to the Marshalls....not quite sure how I would deal with that if I was one of the runners but it would not be pleasant. So I am relying on the 30,000 in front of me in Berlin to follow the right course ...I want my medal!
I ran Paris 2011 and 2012 and such happy memories...very excited about the prospect of Berlin and then I remember I need to train ....struggling to motivate myself on distance but embracing interval training ....I am sure come June I'll be up with you all with positive noise ..or atleast I hope I will