I should've listened to warnings... My friends who played this game warned me that it's bad and it's going to put me off the AC series. They were right.
I'm not going to complain about the optimisation and technicalities. It's not horrible, playable even on my old-ish rig. My main issues are:
1. Dull plot.
It's difficult to care about the protagonist or his plight. The prologue of the game is actually reasonably interesting plot-wise (albeit definitely too long - takes almost 3 hours!!!). After that, it gets worse.
Not sure, might be the fact that I'm not American so I don't really care much about their revolutionary history - apparently most of the people Conor meets are somehow famous, but since I recognise only a few names, I can't feel excited when he meets yet another guy who tells him how important it is to do this and that and yadda yadda yadda, ZZzzzz.
What's worse, it's not entirely clear what the conflict is. Seems assassins want to kill templars only because they are templars, even though their goals in the colonies are somewhat aligned (getting rid of the Brits) - most of the time it looks as if Conor was fighting the templars because he holds a grudge, nothing more. Anyway, the plot is slow, uninspired and dull. If you thought Revelations had poor plot... this one is much worse. Revelations at least had an interestig city. Cities in AC3 are almost identical, bland and boring - absolutely nothing to look at, and famous spots look nothing like they now. Seriously, who thought setting the game in the British Colonies was a good idea?
2. Game construction and mechanics.
This is just frustrating. Short walks or runs frequently interrupted by short cutscenes that don't really add any value. Then another short walk, another cutscene. A short fight, then a short walk, and a cutscene. Aaaargh! And it happens very very often!!! There are way too many missions where you have to chase someone, or tail someone, and soldiers tend to get alarmed by your presence for no apparent reason. Controls are clunky, after 20 hours of game time I'm still not entirely sure how the fighting system works and you don't really have that much assassinating to do... Oh, and parcouring in the forest - BORING and silly.
Also, this game feels like the most restrictive of all AC games so far. OK, in all of them your option to kill the target were seriously limited (it's not Hitman after all), but this one is totally ridiculous at times with laughable stealth and frequent instant failures. Feels extremely linear too but the most annoying fails are caused by stupid bugs, like Conor sticking to walls and buildings because game developers decided it will be a great idea to have running and climbing under the same button...
There were numerous moments where I considered giving up after yet another fail for stupid reason like that, and just watchning the rest of the endless cutscenes on youtube. I even attempted that once, only to find out (to my relief) that I'm nearly at the end of the main story, so decided to get on with it. Phew. And as I said - the story is dull and the only reason why you may want to actually suffer through it is to see Desmond's fate and for plot continuity before I move on to AC4.
3. Shedload of stuff to do but none of it worth your time.
You can hunt, trade, expand your homestead, attack convoys, craft stuff, take control of city areas, conquer forts etc. The problem is - you don't really feel like it's worth your time. You won't get much out of it. Some money, that you can live without. Unless you're an OCD sufferer who just needs to do every single mission and achievement, you will completely ignore those side-subquests. The game will, of course, force you to suffer through some of them just to show you that you can do them, but after that... you'll most likely ignore it. Kind of like the tower defense part in Revelations - after the tutorial you probably never bothered. AC3 has about half a dozen useless elements like that.
Having said that, the only element that seems less boring is sailing. True, after a few missions the novelty wears off as well, but at least it's fun (no wonder the fourth game expanded that part) and there is some sense of achievement when you sink a larger vessel. Expanding your ship is very tedious though, as it requires a lot of money and the economy of this game is just broken.
Previous game had this neat system where you simply rebuilt shops, banks and whatnot and were getting the income from those. Here, you have to craft stuff with some ridiculous and tedious crafting system, then you need to sell stuff via trade routes and such, you can send assassins to do missions but it's nowhere near as simple as in previous game... All this feels like an intentional timesink and amounts to sheer frustration - it's really been a while since I played a game that annoyed me so much.
If you enjoyed previous AC games (even Revelations) - stick to them. Skip AC3 and give AC4 a try - apparently it's much better. Although me, after finishing AC3, I will probably have a short break from the AC franchise. Material fatigue ;)