Alright - so sideloading is insanely easy. Like trivially easy. I basically found an ES Explorer apk online and put it into my Google Drive, then downloaded it to the OUYA and opened it with FilePWN to install it, and then I'm able to send whatever I want directly into ES Explorer from another Android device. Piece of cake.

But I still wanted the Google Play Store - so I rooted and installed it. Riptide GP2 looks amazing but has crazy controller lag that makes it unplayable... But things are looking up, gents! Thanx a bunch!