I just did a post about this game, I think someone was playing it free on PSN or something.
I think on its own it stands as a great game. Not superb, but a lot of fun, and polished. The gunplay has a good pace, controls are responsive, soundtrack is awesome and everything came together well. It really feels like the period and location it's set in. The swamps look like hot and sweaty places to be.
Progression was not as grindy as what people made it out to be, relative to other open world games these days. As long as you're not a completionist, you'll get the things you want quick enough. It is much more repetitive compared to the first 2 games though. In fact, the game feels more like a sequel to the Godfather games rather than the Mafia games.
So, you have a sequel with less variation, but a vastly quicker pace overall. And you have the first 2 games, which were much more story-driven. More memorable things occurred, and stayed with you, whereas in Mafia III, the twist happens near the beginning, and that's pretty much it - the rest is predictable. Mafia 1 and 2, in more typical Mafia movie fashion, had their twists or big moments at the very end, I think even after the credits in the case of the first one. Being built around the whole typical Mafia "crime does not pay" vibe, they each bring you up, and then also come crashing down towards the end. But Mafia 3 is just too much of an outlier - it's a good game overall, but doesn't do any of these gameplay elements particularly well.
I only played through each game once, though I can remember more about the city, the people, and the story in the first two games than the last one, even though they are quite a few years earlier.