What you can do already as an interim step is to use smart rules based on list membership, at least for the subject line and the body text of the DOI email.
The only problem with this is, that in some cases the DOI email is sent before the contact was added to the smart list, so this way is not reliable. Those contacts will receive the default version. If this could be fixed (e.g. by delaying the DOI email for a second, I would personally be ok in a first step).