If I am not mistaken, Aron is the first actor to have appeared in seven season of a Trek series to have passed away.
Majel Barrett (TOS 1-3, TAS 1-2, TNG 1-5 & 7, DS9 1 & 3-4) has 14 seasons (and two movies) just between her appearances as Chapel and Lwaxana Troi. Add in her voice over work as a Computer Voice, and you cover every season of TOS, TAS, TNG, DS9, Voyager, and the last season of Enterprise. That's 27 seasons and a total of seven films with her involvement in some manner. It'll be awhile before someone tops that.