We would love to see this too - basically the same endpoints for the Teacher Role as we have for students when looking at activity and participation in courses.
@lmurray2 - in the meantime, what we are attempting to do is cobble a Teacher Participation report by looking at common teacher activities (entering grades, submission comments, updating assignments, using a rubric, etc.) that are present in the DAP table schemas. It's less straightforward than querying the API (you have to download all the incremental data you want from the tables, convert it into something readable, then filter for the information you want) but you can get pretty granular. And if you're comfortable using something like Node.js a lot of that can be automated with JavaScript.
Ask Your Data can probably do a lot of that for you in the GUI, but I like having the raw data too.