Hey, that's the dates they are playing with VNV Nation, aren't they?
How many shows do you wanna attend? If I were you I'd probably go for the Berlin-Magdeburg-Dortmund-Hannover route. Basically you'd go from east to west with a 2-3 hour journey everyday. Berlin is of course easy to travel to by plane and you could do the rest by train.
Krefeld-Erfurt is a much longer distance, not sure I'd recommend that.
I see Berlin is on a Friday night, so you'd have a night out in Berlin after the gig which is surely not a bad thing!