Think about the possibilities. Think outside the box.
What's one of the oldest and standard way of controlling a game? Game controllers. You want to use game controllers? I'd use a simple way : make a simple executable container catching game controller's inputs and sending it to the inner-browser as keystrokes.
That is only idea #1, and I've got plenty of them so far hehe, like publishing. Publish on Steam, on download websites, etc.
And don't worry, I'll stay on C2 ;-)