It is a fantastic game as its very close to the original, however I find faults because of the things that they removed from original mafia.
It's been a whole but off the top of my head, monorail is gone, that mechanic you go visit gone? A few missions are simplified. The barn one in particular is just "go straight to this marker" instead of, find Sam within the area, leaving you to explore and get ambushed.
You could also kill morello (was that his name?) in different ways in the original, even missing the entire airport level.
To be clear, these are minor issues in the grand scheme of things. It's still a great game. I'd like them to make mafia 4 to follow on from this game, or even better, be a prequel to the story of the 2 dons.