The one caveat, you will need a toon of at least level 55 on the account before you can make a death knight on the account.
Unless they changed that.

Still, 3 levels per Death Knight as grants (upon attaining 56th, 58th and 60th levels), and to any 59th or lower toon on the team is certainly decent. And you can delete the DK's and repeat as much as you like.

Most of the quests are quite group friendly.
Stealing the mount is probably the only quest which wasn't group friendly.