Build the robot you want to build, and don't worry about TV or any other considerations - Robot Wars the television show is fantastic, and everyone wants to be on it, and it provides a good impetus for me to keep progressing with Swift.
But robotic combat as a sport was here before the show, and will be here long after it's gone, so my advice is honestly just to focus on whatever idea or design or weapon makes you happiest. Remember, it's meant to be fun