I know not everyone is a keyboard user, but several of us are.
When I clear an activity and assign a follow-up, I can close the Follow-uyp window with an Alt-O (OK). It then drops me back to the Activity window, but only a mouse can clear the "OK". The user can't do another Alt-O, which would be a very quick step.
Steps like this and drop-down menus are still inconsistent throughout the program.