Are you working on either a custom mythtv-frontend or a new theme for the present frontend that would more closely match your orbiter themes? Or, a new orbiter theme that would match the myth theme?
I actually would almost prefer the orbiter theme idea. Is it possible? Provided things stay consistant across orbiters...
I think that using Myth for your backend is a good idea. I also think that you could
possibly use more of the myth addons, like myth-game, myth-weather, and myth-video.. I don't see why you have to reinvent things, like your video and audio stuff, when if you could have found a way to more closely integrate into the myth stuff... Granted I'm coming into this fairly late in the game, and I'm sure you had good reasons, not just the desire to "own" the source.