Single Status Update
Finally got my Game Boy Player setup up and running today. I've forgone using the GB Player disc, because a) it's expensive and b) it sucks ass. Instead I'm using the Game Boy Interface homebrew via an SD Card Launcher for GameCube! I need to get RGB SCART cables for actually good video quality, but I'm happy I have a setup for playing GBA games on my monitors through original hardware now.
(I also learned that you can actually run entire GC games off MicroSD cards, which is... terrifying.)