I'll give them credit, the trailer didn't suggest anything too outlandish or over the top. Maybe the Ecto-1 "door gunner" ... but overall it conveyed a grounded narrative. Or, as grounded as one gets with a story about busting ghosts.
Especially when compared to the train wreck of the last film.
Who knows what the movie actually is, or at what point it will come off the rails and devolve into the usual Hollywood drivel. The original 1984 Ghostbusters was an action comedy. This trailer lacked any serious hint of that, instead appearing more serious without the camp and slapstick.
Even though we're dealing with a young protagonist as lead cast led by an adult, which totally reminds me of Stranger Things, probably helped by casting Finn Wolfhard.
Dan Aykroyd has been toying with story treatments for Ghostbuster films in which the Ghostbusters end up in another dimension to fight paranormal evils... this was the original idea for Ghostbusters 2, and Aykroyd wrote an outline for GB3 that had the original cast in a mirror-dimension called ManHellton. These ideas ended up on the cutting room floor and were not used.
This version is titled "Afterlife" maybe in reference to resurrecting the franchise, but also (maybe) because they end up on the other side of a portal, in the afterlife. Very "the upside-down" from Stranger Things.
Murry, Ankroyd, Hudson, Weaver and even Potts are supposedly cast in it... probably a cameo, maybe a little more than a cameo (fingers crossed).
I doubt they'll "reanimate" Ramis with CGI as a ghost... though he might appear in flashbacks using original film. I don't think it would respectful to do otherwise.