I propose in Blast Arena, if someone gets 10 points ahead of everyone else (could be a lower/higher number), the default bonuses at respawn are increased by one (so if everyone normally spawns with 2 of everything, it immediately ups it to 3). This would make it easier to kill the leader and get rid of his huge bonuses so other people can actually get kills. If the leader really is that good, he should be able to hold his (already huge) lead as he respawns with the same boosted bonuses, but at least there can be more competition for kills (and a slight chance at someone catching up).

If there's a runaway leader in the game I'm in, more often than not I'm that leader, so I feel I can safely say the game is boring and unfair if it gets to that point.