I think you demonstrate my point beautifully Pete, allowing riders to name their own rides means that within the parameters of the available rides you can customise, like your "big chicken" ride.
Personally I'd like to do an SS1600 encompassing all the Murray river ferry crossings between SA and Victoria, once I figure out a way to verify that I undertook all the crossings. But I'm happy for my customised run to sit within the parameters of an SS1600, just like your "big chicken run".
So if we leave the meeting alone, riders have the flexibility to include it in a multiple of IBA rides, thus respecting the integrity of the meeting and giving them more flexibility in celebrating it.
Looking at your list above, it looks like plenty, with the ability to customise. A couple of 'special' rides like the heaven the hell and that's plenty. Let's not go down the Yanks road with a,bewildering array of rides. Or at least, let team IBA Oz give careful consideration to each new ride we add so they really mean something to a wide variety of people in our pursuit.