I'd take the F10 5 Series. Don't worry about it being too big - it will have great seats that will adjust perfectly, shrink around you as you get used to it, and the base spec comes with parking sensors front and rear making it easy to maneuver around. What exactly is the 5 Series option?
Probably the 520d SE - pretty awesome spec for a base model, heated leather, parking sensors, latest iDrive, etc.
Hoping I can stretch mine to the 520d M-sport, not looking too likely though!