#1 A Superstar debut or return SHOULD take place at TakeOver: In Your House

One thing that should happen at TakeOver: In Your House is a big debut. Before the pandemic, debuts were the norm for every TakeOver event. New performers either showed up in the crowd or inserted themselves into an ongoing angle.
Adam Cole debuted alongside O'Reilly and Bobby Fish by attacking then NXT Champion Drew McIntyre. Bobby Roode and Asuka showed up in the crowd during other TakeOver events.
Cody Rhodes' uncle is a WWE Hall of Famer. More details HERE.
LA Knight debuted on the pre-show for TakeOver: Vengeance Day in February. To make a bigger impact, any debut at TakeOver: In Your House needs to take place during the actual PPV.
With the dissolution of the Undisputed Era, the main factions in NXT are Imperium, Legado Del Fantasma, and Hit Row. Hit Row was recently formed and needs a push to be taken seriously.
With so many heel groups in NXT, there needs to be a faction of faces to oppose them. It works when the likes of Bronson Reed and MSK team up or when MSK and Kushida join forces. With more than one bully to take on, however, more permanent alliances are needed.
Vignettes for the Diamond Mine have been airing on NXT TV since late April. WWE trademarked the name in December of 2020. It could have been for a new faction or a new concept. The latest vignette claimed that the Diamond Mine would be "opening soon." Could that be at TakeOver: In Your House?
If the Diamond Mine does not open at TakeOver: In Your House, then a new performer must make an impact. Franky Monet debuted a week after Stand & Deliver. It offered up a big moment for NXT immediately following the biggest card of the year for the black and gold brand.
As things slowly return to normal following the pandemic, why not use a time-honored tactic like debuting a new Superstar? Tegan Nox could make a surprise return after suffering another knee injury last year.
Perhaps a star from NXT UK will make the official move to NXT. A former standout from Evolve like Josh Briggs or Joe Gacy could appear. There needs to be some sort of surprise at TakeOver: In Your House. It could be in the form of a debuting or returning star.