Who?
Just the Doctor
controlling your TV might not be one of them. It typically uses your TV as an output device and that's the extent of control it has on it. You could look into using an irblaster in conjunction with your frontend to exert more control via scripts that can be tied to your remote control using lirc but that's something you'll have to build yourself. It's more common to use an irblaster for channel changing a cable box for which mythbackend already has support.
I'd say pick whatever TV works for you and ensure your frontend can handle decoding and playing full HD content. Add a universal remote to the mix and you have the makings of a killer mythfrontend. If you'll have a separate backend (which is what it seems like based on your description) you won't have to touch the backend at all.
UNIX was not designed to stop you from doing stupid things, because that would also stop you from doing clever things. -- Doug Gwyn