Alec, I don't think that the movie franchises are being overplayed. With the omnipresent media options we have available these days, we've become an ADD society, and ride developers have no choice but to go for the biggest bang for the buck as quickly as possible and hope that the ride reaches "classic" status before it becomes generationally obsolete.
I'm going to slip into "old man" mode for a minute, and point out the differences between how entertainment is delivered now versus how it was in the 60's and 70's when folks like me and Robert Niles and James Kohl were still looking for the prizes in the boxes of Crackerjack.
Good movies showed on usually only one screen at the movie theater and they were there for months. Now movies are on multiple screens at the cineplex in 2D, 3D, and IMAX for only a few weeks, and within a couple of months or less are available on streaming media and DVD (for the old folks and the technologically challenged).
You rarely heard about overseas box office revenues in the 60's and 70's. Now they are considered as important or more important than the domestic gross to a movie's success.
Cable was limited. Home computers were nonexistant. The internet wasn't even a DARPA dream project yet. VHS tapes, DVDs, and digital tv? Nope, nope, and nope.
Merchandising was limited to lunchboxes, coloring books, and pencils with the occasional doll, action figure, and board game on your birthday or at Christmas. Nowadays, it is an onslaught of movies, books, coloring books, comic books, cartoons, clothing, computer games, DVDs, soundtracks, action figures, dolls, bedroom furniture and accessories, birthday party theming, Happy Meal toys, cell phone apps, and every so often you see a themed lunchbox or pencil.
So, in reality, theming rides to movies isn't really being overdone. Themed consumerism is being overdone.