I would be mortified if they brought Han back. He got (earned) an incredibly poignant death scene. But, I’m convinced we’re going to see more of him either in flashback or one of the anthology movies.
I’m still not sure how I feel about flashbacks in SW. It’s really ‘un-SW’; these are simple movies and they’ve largely eschewed narrative devices like that. And we know he’s not coming back as a Force Ghost, so that only leaves so many avenues…