While the talent for Vegas is clearly there (abundantly), I could see it being too much of a shake up in the middle of the season. They added 3 players. Hertl is gonna have to hit the ground running learning a new system coming back from an injury late. There's gonna be a lot of line shake ups. Stone's injury, people in and out of the lineup, etc.
It's a lot to expect from a team. Systems and chemistry can take time to learn and yes, that goes for all trade deadline acquisitions, but it's a little excessive and I think all the juggling might do more bad than good.
With that said, Hanifin added to that already great defensive core and a great overall defensive team is a huge add and my favorite of theirs. Not saying they don't have the ability to repeat, but those are some questions that are worth asking.