I appreciate that you want to make the round fun and memorable, just remember that less is more when playing special rules like that. Ideally, you want a ruleset to be entertaining but not really powerful enough to affect the outcome of a game. How fun is it if somebody's favorite player gets blocked into a box and it explodes, killing him? Or if Sandy Claws goes on a rampage with his random movement and injures half of one team, leaving the other untouched?
I'd try to consider something thematic but with less impact on the game ... even something as simple as "Weather starts out as blizzard, instead of rolling random weather" or "Every team gets a christmas tree token which can be used once during the game as a reroll".
Having played in the league and accepted the rules of balls turning into jet engines and exploding, or inflating or pit traps that catapult you halfway across the pitch I think we all accept that these things can and will happen. Round 2 involved one of our players getting very drunk showcasing booze for th sponsors and potentially throwing up down himself and gaining foul appearance as well as dauntless. very silly but lots of fun!