I use remote control with lirc and I use smplayer tv:// -fullscreen in my lircrc file.
But after executing it I found (previously unchecked) Start videos in fullscreen option in Preferences->General->Video.
I think it's a bug and smplayer haven't to enable this option globally when using -fullscreen argument.
Also I think it will be a good idea to have separate fullscreen / panscan / video_filters, maybe some more options for TV mode in Preferences->TV and radio.