#1 You can spread it out over a few weeks

You can't really call it the World Cup, since that's not what it really is, and also since they already did that for last year's Crown Jewel event, but it's an intriguing concept. TNA, for many years, did things like the World X Cup, which saw teams with representatives from all over the world compete in different types of matches over the course of a few weeks to determine a winner. There weren't a ton of stakes, but it was a fun, exciting, and different concept. There were singles matches, tag matches, Ultimate X matches, and more, and it was one big event spread out over the course of a number of weeks.
Instead of relegating it to one night, why not spread it out? WWE always has a down period following WrestleMania and there's a bit of a lull in the action before they start ramping things up again for SummerSlam. There's Money in the Bank, but I would argue that MITB could move back to WrestleMania in order to allow WWE to run a series of different match types on RAW, SmackDown, and NXT television throughout the month of April and into early May, culminating in a big PPV event at the end of May in which the finals are held.
Do something completely different. Use a points system. Use all sorts of different match types. Going this route gives you around six weeks of entertaining, special television that only comes around once a year, and comes to a conclusion with a big event that crowns winners for different things. The winning brand gets something, such as their choice of wrestler (or wrestlers) to join their brand, maybe take the championship from one of the losing brands and make it their own -- the possibilities only end where your imagination ends. Certain Superstars could get extra rewards by being the MVP for their brand, such as a title shot at the championship of their choosing, and so on, and so forth.
Why limit brand warfare to one night?
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