Pete: I think I addressed this with my falling putt argument. IMO making violations obvious and infrequent will do a great deal to remove the perceived stigma in calling them. I've rarely seen an overbalanced putt inside the circle not called, maybe a couple of borderline ones where balance was dubious got a quiet word on the way to the next tee instead, but the majority are called.
James: The marking is not tied to it, it's quite possible to implement the rest with the existing marking rules, however I disagree on the uncertainty argument. The vast majority of lies would go unmarked as it would only be only necessary if you wish to use the thrown disc, or are already marking where the disc is not (OB, above/below ground). So most lies would be more certain, as you'd use the disc exactly where it lies.
Additionally, using the thrown disc is a far superior visual indicator of the lie area, you almost have to have some part of your foot behind the 'shadow' of the disc.
One man's gripe is another man's ridiculous
But it's not something we've even talked about.
I'd be interested in thoughts on size/shape of the lie area. Is 30x30 small/right/large? Square or circle?
Also the concept of a fairway marker at 30m instead of a circle as per Ricks suggestion. This would mean that if you overshot the basket by >30m, you cannot follow through on your return shots.