I work at a radar facility that works a lot of aircraft from C152's, corporate aircraft, to airliners that do pratice approaches on a regular basis (ILS's, VOR's, NDB's, GPS, and Back Courses, and the always enjoyable ASR)
Running a sequence with multiple acft some doing the instrument approach and some on a visual approach and with varying types of aircraft and speeds and to crossing runways, does tend to get challengeing.
AT FWA we let the tower issue alternate MA instructions because we don't want the pilot doing the published missed and tangling with another acft.
Mike