I think I've finally cracked why this is such an inferior sequel.
The score is dreadful. It's not the same composer from the original.
Ditto for the cinematography which is also not up to scratch.
But the main issue- the city is not threatened like it is in the original. Sure, ghosts turn up but the threat is mostly to the Ghostbusters and Dana. It's what makes it weird at the end with them being given the key to the city. It's not like the killed a rampaging marshmallow man - they just made some slime come off a building.