Have 2 sessions of big Battles Royal a year, instead of 1. In addition, have some smaller Battles Royal for the smaller maps, perhaps even just on the special occasion maps and perhaps just for premiums.
Have 2 sessions of Battles Royal a year. Just like now, only 2 instead of one on the bigger maps.
In addition, allow premiums to play Battles Royal on the specific themed maps for special occasions. Each person would only be able to play in one Battle Royal, to keep it from getting out of hand.
How this will benefit the site and/or other comments:
Just offer more excitement, and a real holiday bonus for premiums, since premiums already play speed games. I can concieve of 1-2 people going premium just so they can play in these games!