It would be very helpful to be able to export multiple assessments in one report. If you have a course with periodic knowledge checks as assessments, it would be great to not have to navigate to each assessment individually, then click "assessment activity", then click export and choose a format, then download, then go back and do that multiple times just to get a report of all knowledge checks associated with a single course.
The assessments screen already looks like you should be able to select multiple assessments. Please allow admins to select multiple assessments for the assessment activity report!