I like the idea... My suggestion would be to just pick some events. e.g. a deadlift event, a bench event, a pullup event, 5km row, 5km run, whatever... and anybody can nominate for any event.
If there happens to be major interest in a certain event, you could split it into age/weight categories.
Have a point scoring system for an over-all winner.
Hand out gold/silver/bronze names imo.