Marc de Vries writes:
2) The case for bringing tapes off site is more difficult to defend.

I would consider taking the backups home with you a serious security
issue. Those tapes contain important data that someone might want to
steal. I assume that your office is better protected against burglars
than your home?

That can be handled rather simply by encrypting the tapes. If someone
steals them without the decryption key, the data is inaccessible.

The parable/marketing blurb at http://www.taobackup.com is well worth
reading for anyone in the OP or his PHB's situation.