Populating Invitation Email with Additional Data

This might be a lot, but I have an application so I thought I would put it in here.

Let's say I create a custom invite list that has additional fields, like supervisor. It would be really helpful to have the invite something like:

Hi {NAME},

You are invited to participate in a survey about how well {SUPERVISOR} has empowered you to do your job.

Click here to take the survey:

{SURVEY_URL}

This would necessitate having a process to import custom fields and push them to the email creation form. I haven't yet imported a file to know how it handles additional fields beyond name and email.

Thanks for your consideration!