This only really applies to cruise ships, but have one scheduled character meet a day in the adult only section for adults only. I know that in the kids club they get exclusive character meet and greets which is great for kids who may not want or be able to do the chaotic fast and crazy meet and greets in The Atrium area.
Having one adult only character meet and greet would also make the The Atrium area less in demand, as currently adults and families all queue for the same character meet and greet.
The Southampton Dream sailings in particular this summer had very high demand for character meet and greets, so much so that some characters were withdrawn from the Spain itinerary.
Although, I'm sure we all know that there would be complaints about an adult only meet and greet, as you know, Disney is for kids, rolls, eyes, sighs. And there would be the entitled mom who would insist on her special kids doing the adults only character meet and greet.