Whatever you do, no more triple stack playfields on top. If you want three levels do it like Krull and put a full scale 1/2 size playfield UNDER the playfield with a special lens in the main playfield so you can see the whole thing with normal physics and then a small playfield on top of the main playfield.
If you want three levels, that is. I'd be fine with two.
But really, Scooby Doo is the easy choice because it has terabytes of content so little animation would have to be done to smooth out the UI and modes and there are tons of celebrity guest appearances plus massive nostalgia across all age groups.
scooby doo teal (resized).png