"that the majority of businesses are running Office XP, Office 2003, and Office 2007"
What a bunch of rubbish. Did that include the companies here and around ours? No, it didn't. We use Office 2013, with two people on 2016, as Office 2007 is far, far too old.
We're also thinking of office 365, with Exchange, in order to remove the Exchange servers from the network and to then install the latest version in two ish years.