While 100’s of players on massive maps for a day long milsim wargame can be a wonderful experience and I have personally always thought more players = More targets.
The reality is more fun can be had with lesser numbers and smaller arenas.
Lesser numbers = Easier/swifter player prep & organizing = More games = More lives/deaths = More fun.
And with a whole day of play many types of games can be experienced throughout one day.
And highest in fun type would generally be any respawning games set to a time limit although they can be tiring, but a great way to start or end the day.