Would like to echo the above

As for specifics, I think a 75% rule would be fair or just some kind of common sense ruling - just so that someone can't hide an antweight in the arena to avoid being counted out.

Also would like to have the walker/shufflers mentioned - robot wars weight limits on those would be great globally, maybe a slight increase on either just to make them more viable - something like a 15% and 30% increase for shufflers/walkers respectively? Nothing too huge but enough to make them a reasonable trade-off for the lesser mobility and higher difficulty...