It's mid, yeah. Which is horrifying to say due to all the labor that went into it. The ultimate result is mid.
I bounced off it twice and eventually stuck with it by not trying to play it like MGSV. The game doesn't actually give you any freedom. There is no connection between the missions and free-roam in the overworld. Once I stopped trying to struggle out of the shackles and just treated it like an on-rails movie it got a lot better, if you can handle that. But it is just so long.
The best time I had in the game was hunting to get all the camp & pelt upgrades. Being in some beautiful scenery hunting down particular animals is pleasant, even though the long animations and requirement to constantly bring your pelts back to camp irritated the shit out of me (even with fast travel).
The story just fuckin drags. I got to the end of the main story like a year ago and haven't got around to playing the epilogue yet. The fact that you murder 100 random people every mission in the game but the story is about how you are trying to redeem yourself for beating a dude over some debt is just fucking stupid.