My sister and I have been playing this game for quite some time since we got it on release date and we've found it extremely enjoyable so far, and I dare say it's my favorite of the Luigi's Mansion games. I've gotten into the game without watching any sort of gameplay footage whatsoever, playing it blind, which I tend to do. It pretty much plays like a Luigi's Mansion: Dark Moon sequel than anything else but I'm okay with that since I really liked Dark Moon much more than the original game; in fact, generally speaking it's pretty much typical Luigi's Mansion stuff but with extra moves, but I've always wanted more Luigi's Mansion stuff so that's great.
Local co-op with my twin is a god-bless feature to have thanks to Gooigi. We both have plenty of fun exploring around the hotel, even though my sister tends to constantly stick the plunger on my head and multiple lolz attempts to spawn in the rain only to melt down.
The game oozes with charm, and you most see it in the opening cutscene. Characters are extremely expressive, and I love the subtle stuff you find in the character's rooms such as Red Toad being a golfer, Blue Toad liking music, and Yellow Toad loving dessert, and of course, Mario having a love of food. When I destroyed their luggage in their rooms (naturally), this is my only reaction to what's inside them.
Which I think makes the lack of dialogue from Mario and Luigi all the more jarring. I know it's been...Mario series tradition to sometimes not give them dialogue, sometimes do, and it's consistent from Luigi's Mansion games and in general to have characters speak their thoughts but christ sometimes I wish they drop it because it ultimately acts pointless when the characters they're talking to just speak out their thoughts anyway (it wouldn't be any less awkward if Luigi directly told E. Gadd, "My friends are still in the mansion, we should stay!" rather than E. Gadd just repeating what he "said". They even gave Peach a one-liner in the opening that she could even not have spoken dialogue at all.