The problem with no gap is that a reliable rambot has the greatest advantage, they just bounce around the arena untill the other person breaks, they have this arena type in America and they've all evolved to boxes, and has less vereation than the uk.

I think a vearation of arenas could be used to created a wider range of robots, as different types would excel in different arenas so more veration would be created.

If there ever was a no flip out arena in the uk you would probably have to have a mandatory weapon rule (but with rambots over a peticular speed, as then they can be argued to be classed as a full body hammer, excluded from the weapon rule)