A couple followup thoughts:

After watching The Enigma of Kaspar Hauser, I got into reading the wikipedia page for the real Kaspar Hauser. That dude sounds like a lying bastard. I'll take the Bruno S version any day.

Also, an extension of my Nic Cage thought from earlier: there is a brutally honest and metaphorical truth to be found in a film where Nic Cage plays a famous actor who buys a European castle to save it from decay, goes broke and then takes creatively unfulfilling, miserable, big-money roles to make his money back to live his dream.

Expect me to keep pushing that idea until it happens.