Since your market launch will be directed to non-BYOD users and is defined as residential, I personally think this sounds like a good idea.

You would expect that many, if not most, of the new sign-ups never had VOIP service before and therefore a wizard would serve them well. I think you would save countless hours for your support team if they are required to fill in the blanks before going forward..and even if they have been in the VOIP world, you know how differently every company runs their programs.