I don't see how it would be full of nostalgia bait again. Afterlife was a very good relaunch, they tried to please old fans while introducing the new generation, I have a good feeling the sequel won't be that much shackled to the past. I mean we'll obviously get fanservice with the HQ and maybe some cameos but it only makes sense, and idk, I feel confident that the heart of the movie will be fresh.
Personally I'd like if they tried to go closer to the tone of the original but that may be hard with a young cast. They can reach for it though, give it a new spin.