All manufacturers attempted to create original ideas, with varying degrees of success. Look at some of the GREAT ideas ;

Cirqus Voltaire
Medieval Madness
Cactus Canyon - Rubbish game, but good theme
Junkyard

Go back in time

Paragon
Fathom
Black Knight
Black Hole
Haunted House
Freefall
Solar Fire

Even further

Spirit of 76
Buccaneer
Card Whiz
Surf Champ

Original ideas - No "safe" ideas at all. The most iconic and successful period of pinball rarely had any reference to movies. They were original ideas. That was one of the appealing factors that made pinball part of society. Now, manufacturers like the "safe" titles, but they restrict themselves by doing that.

Movies fans are their target audience.

Whoever has the innovative idea of a completely original theme will not box themselves into a target audience. They would open it up to new markets.

I would buy a Cirqus, Horror or Medieval theme - or at least be interested. I have no interest in Movie pins, but I understand why they are so popular.

I think an original theme centered around Race Cars, Hot Rods or similar would be a big hit.