It's not necessarily a bad game, it's just all the really bad decisions they did for this game that made it into the pile of dung it is now..
For one, they took a lot of features from Shogun 2 and previous titles completely out of the game, like the really cool in game agent cutscenes and ANY detailed political systems. There is literally zero innovation in this game, apart from the land/sea combination battles and a new camera angle that sets you literally on top of a unit so you can see the fights properly, if you can even call them fights.
I could care less about the graphics and animations, but the actual gameplay and immersion for Rome 2 is so bad that it literally has zero replay value. You can polish a pile of crap all you want but in the end, it will still be a pile of crap.
Hell, Empire was a pile of ****, but it was going where Total War hadn't gone before with Naval battles, the new province systems with more modern weaponry, and so on. Honestly, as someone who started with the original Rome and played thousands of hours on it, Rome 2 is a disgrace of a sequel.
Kind of Harsh, but After Vikings: Battle of Asgard, Empire/Napoleon, and the success from Shogun 2 I would have thought CA would have learned some lessons. Apparently not. Oh, and the first expansion is already announced