[account42]

a) This is only for commercial websites although what counts as commercial is vague and probably not something you want to argue in court so it's safer to just add it unless you are absolutely sure.

b) You need a valid postal address where you can receive mail but this doesn't have to be your home address. A PO box is fine.

c) You don't need to have a phone number in your Imprint.

The base requirement of commercial operations having to have valid contact information (that can be used for legal communication) is pretty sensible. The details could be a bit friendlier towards individuals running purely personal sites.