Love the idea of zones and making modifications to the robot to suit the zone you'll be fighting in. Scrappy Races meets Crystal Maze. Logistically it would be more challenging but it would require adaptability to be designed into the machines. That in turn could have the benefit of keeping things fresh or interesting as you're never fighting with (or against) the same robot each time.

On the flip side, I'd also be happy with a straight shoot me up like the current Battlebits format. Downside of that is said format can get boring after a while, and it could be finished again after a few series depending on how it progresses.