Best-sellers tend to be shite, though. And most of what you're talking about as "mainstream stuff" is the movie-making equivalent of best-seller books.

Don't look at the heavily-marketed stuff. That's like the "best-sellers" rack at the bookstore (or the "Recommended for you" section of book-selling websites, equivalently). Look for the stuff that doesn't have billion-dollar budgets, big-name stars and advertising campaigns that cost more than many small countries produce in a year.