First of, love it. This is now replacing Ultimate Member for me as we only used it for the Notification Center more or less. So that is very nice.
Two requests though;
1 - I would really like to see the Notifier option to be the User's avatar. As that makes more sense for interactions. For guests we could use the a default/gravatar like fallback.
2 - This is really just a nice to have, I would like to the option to have a link to the users profile/author page.
If not possible, please guide me to a hook/filter which I can to get this done, I dont' mind doing it myself.