Hard to say. The game is nothing like any of those.
It plays totally like Sea Dogs and it's sequels and spinoffs:
Sea Dogs (2000)
Pirates of the Caribbean (2003)
Age of Pirates: Caribbean Tales (2006)
Age of Pirates 2: City of Abandoned Ships (2009)
And it seems totally inspired by those as they share:
- superb music
- clunky groundcombat with horrible opponents AI
- bugs that prevent some quests from being solved (I hope this was fixed in RC:EE)
- totally fun ship fights
Differences?
Unlike Sea Dogs and the rest, you can't "improve" skills of your ship officers in Raven's Cry - skills they have by default never change. This is not a bad decision IMO as keeps you away from grinding since RC sidekicks don't really have BlackIsleish background story to share.
You also can't make a fleet and lead it with you in Raven's Cry (apart from friendlies that temporarily join your side during some quests). Another good choice as in Sea Dogs you could build an OP fleet and pwn everything.
IMO you should first test your taste with DRMfree Sea Dogs available on GOG:
http://www.gog.com/game/sea_dogs
No need to rush, you may grab it on xmas sale and of course, because TW3 and FO4 who has time for other games now?
Is Raven's Cry EE a musthave game? Dunno. For the original game I already said it's slightly above average after I finished it. For enhanced edition still can't say anything for sure as I barely started it and barely scratched the mainstory as am enjoying new sidequests.
To this day I don't know why critics panned it so hard. I've seen many games in my life and some definetly deserved 1/10, but this one totally didn't. And critics were showering the game with that score calling out whatever unforgivable issues seems only them had - not only nonexisting bugs (as I made the actual buglist) but also issues related to the game story (sexism, racism, slavery, etc) like all of them expected kill_noone and remain politically correct Superman game and not an evil pirate in the era where political correctness was a fairy tale.
One thing I can say for sure.
Unlike (usually) overhyped visual candy I've played this year, mainly AC:Unity and FarCry4 where I uninstalled without ever finishing those because of utter boredom, I've finished original Raven's Cry twice without getting bored anywhere and now am on it for the third time, and again not bored to death like with grindy and repetitive modern mainstream games.
Hmmm… I might copy this on Steam minireviews.