“maybe, Apple has some way to figure out if you're installing free apps via XCode or not and it blocks installs if they are from iTunes. Is that something you could look into in a future version?”

Definitely this will go on my todo list near the top. But although I’d love spending all the time this toolchain deserves really on it, I’m trapped with paid contracts that give me little free time and it’s hard to keep up. Sorry for not being able to provide an immediate fix.

Libimobiledevice has tools to install iOS apps over USB. I’d be very interested in your feedback if you manage to install your app using these tools. Do notify me then please.

Alternatively, I’m convinced the paid profile will work.