Said it before, I'll say it again: the game is a masterpiece, and is probably the best game I've played on PS4.
I'm doing my best to burn it slow. Had one session where I left the horse and rifles at camp and just went exploring on foot, walking (not running), catching fish as I went, and camping overnight where I needed to. Spent about five in-game days on this little journey, and I can't even tell you how much fun I had doing that. The world they've built is so lush, vibrant, and teeming with detail.. I have no idea how anyone can call it 'empty'.
And when I'm ready to push the story along, that's also very well done. Great dialogue, interesting stories, well-acted voices.. dunno what else anyone could ask for.
I think people are doing themselves a disservice if they're just plowing through the story. Me, I don't use fast-travel, only use the small compass instead of the minimap, and explore whenever possible. If ever there was a game that was meant to be savored, it's this one. It really rewards you for taking the time to soak everything in.