#2 Sheamus - Would Eva Marie be a necessary addition?

Admittedly, Sheamus is the one that needs Eva Marie the least on this list. He's been enjoying a fantastic run on RAW this year, having feuded with the likes of Drew McIntyre and Bobby Lashley.
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He was constantly hanging over the WWE Title picture but ultimately won the US Championship instead at WrestleMania 37. Sheamus has been great, and adding Eva Marie might only enhance his run and get more heat on him.
#1 Braun Strowman - Is it time for a character overhaul?

This all depends on whether Braun Strowman walks out of WrestleMania Backlash as the WWE Champion or not. Given how things are going, it's safe to bet against Braun Strowman.
Either way, if he was to undergo a major character overhaul, Eva Marie would be perfect to facilitate it. Braun Strowman has remained popular and has a decent character, but there's always something missing.
Eva Marie would fill a big gap that Braun Strowman might need, even if it's only a temporary alliance.