I'm playing it on PS4.
So far I've been having loads of fun, sailing is fun, being a pirate is fun, doing all those assassin things are fun. I haven't had a thing to personally complain about and have no run into any of the issues you have so far.
Really my only wish is to stop being removed from my awesome Pirate game to talk to french people in the future?its a bit annoying.
It does feel a LOT like Assassin's Creed 2, which is the only other game in the series I have played, but I suppose it makes sense it would be similar. I'm loving the whole upgrade my ship aspect and I've gotten really good at dodging those stupid ramming frigates out in the ocean. Nothing really compares to seeing a boat on the horizon, attacking it, boarding it?leaping down from the top of their ship to stab some dudes and loot the all the goods, its all super fun.
The one thing I honestly don't care about is the U-Link shit, no I'm not signing up for yet ANOTHER online service?I simply don't care. I already have PSN+, use that Unisoft, I don't want or need YOUR system for anything.
Really though I have no complaints, its been a really great game so far, best thing to do on the PS4 right now actually.