Subscribe to taxonomy terms without access to 'My Account' area

I'd like to allow users to to Taxonomy terms, but I don't allow access to "My Account". Users should also be allowed to opt-out of a default email triggered by Workflow.

A - When a node changes to certain workflow state, all users are notified,
B - Allow users to opt out via a UI,
C - Using the same UI be able to subscribe to taxonomy terms -- certainly fixed vocabulary terms, but perhaps also free-text terms.

So the problems are:

1 - I use Workflow. This means that nodes are immediately published, so I need to use the workflow trigger/action mechanism to fire off notices.
2 - I'm guessing that all the subscription/notification modules are designed to:
a - be triggered by the drupal core "publication" flag rather than actions, and
b - place the user UI forms inside My Account.

Since mine is a super restrictive site we don't allow users to edit their names, email addresses, organizations, etc. So I imagine a possible solution is to use templates or function to hide unwanted widgets/tabs from the My Account page.

As a side note, I had first looked to do a simple mass email sing an action triggered by a workflow state change, however I now anticipate a need for users to opt-out. Then I realized the need for granular subscription of Taxonomy terms, and so on.

I've looked at Notifications + Messaging, but its placement inside My Account is a deal killer. Another option (which I haven't looked at) is Organic groups, but I suspect the same.

Can anyone suggest an approach for this that allows for just the needs I outlined in a fairly simple, concise UI?