Flighted play is something worth trying for Ams. Ball golf events have used flighted play for years.
Number of flights determined by number of participants and optimal flight-size expectations. 60 Ams, for example, might = 3 flights. Top third plus ties, mid third, remainder. Bigger/smaller field, more/fewer flights. Prizes weighted to top flights, less lower down. Purposeful bagging is difficult as players don't know where the flight lines will be drawn, or how far up/down a particular flight they might end up in.
That's what I'd try if I ran the zoo.