Need Verhoeven Fan Recommendations

Long time fan of Robocop, Total Recall, Starship Troopers, and Basic Instinct. Hell, I didn't mind Hollow Man either! I'm a huge fan of movies all over the world, mainly horror films. However, I grew up on Arnold films and lots of action/sci-fi movies. Naturally, Total Recall and Robocop are among my Top 5 favorite movies of all-time.

Now that I love European horror movies as well as movies from anywhere, I need help here. I want to start delving into Verhoeven's material before Robocop. I want to know if any of his Dutch films are as insane as his American films? Are there any that are graphic? I notice a lot of movies have Rutger Hauer, and I am very curious! Good stories? Action? Thrills? I want to know haha.

Which Verhoeven films are "essential" for the collection? What should I go after?

Thanks a bunch!!