hrmm... Can you do the following:
SEA
sea battles with your own pirate fleet (other players are other ships?)
sea battle combat good?
Everyone is their own ship, so if your have people in a group you have your own armada. Sea combat is OK, but it ends up being a bit of a dance. This might be better if you have multiple people though, as you can different people taking out different parts of their ships.
How many ship upgrade and new ships can you get?
Lots of ships to try but most people stick to a few of the better ones. There are upgrades you can fit to you ship, but there are only 6 different slots. 3 general ones, 1 for sails, 1 for hull & 1 for guns. They do have an impact on your ship, but once again I found that you would be going for the same ones everytime.
Are the main factions smt like english/spanish/portugese/french/pirate?
and can you join them all and progress up the ranks in each of their Navy?
I think its spanish, english, french & pirate. You have to choose your faction at the start and that affects who you can and can't attack. The main difference between them, is that pirates can capture other ships and the other factions can't. This leads to pirates being a bit suicidal in mass battles.
Combat on ships ok? Is it swordfighting left click to attack same as nearly all MMORPGS? What about using pistols?
Worse part of the game last time I played. All you would do is charge for the captain. As soon as their dead the whole crew gives up. Fighting works like WoW, where you get new skills every time you level up. Pistols are one of those skills and you get to use it once every few minutes. Fighting works by using certain skills to put the other person off balance. Once their balance is low, you can use the skills which cause greater damage.
What are the sea and weather effects like?
Mutiny on ships?
Can't remember seeing any weather effect but the sea looks ace. In fact, in the battle screens it looks better than any sea effects I've ever seen. No mutiny from crews as they don't need anything to survive.
LAND
Can you have armies on land (crew) that vary in size depending on your reputation and rank?
Can you fight other armies on land? (ie other player armies)
Can you take over towns and have your flag/colours put up (so you own the town in a way)
can you wander around LARGE towns Oblivion style? Have fistfights in taverns? Get drunk in taverns? sleep with the barmaids?
Can you explore islands for treasure, lost cities of aztec gold etc.
(ie youd get a map to it so you sail to it)
Can you put a mark on other players (ie for bounty hunters to hunt them down and kill them etc) Also would there be wanted posters put up around the village/town showing how much they want you dead.
Special missions for all factions?
First person underground missions?
Land combat consists of you running around by yourself, using the same skills you use on the ships. Again not a strong point of the game.
Every time you go to port, you get to walk around in first person and visit shops and trainers. There are no fights at this point though.
Can you setup your own shop? (supplies/ships/crafting)
You can craft, but it takes a long time to sail from port to port to collect the needed things. You can also setup your own structures to harvest natural materials from a port and then also process it into useful things (like logs into wood for crafting).
The game has a lot of potential, but there are just too many bad points for me to want to get it. If they improved the off-ship segments then it may be worth a play. But as I said before, it will be a lot better if you have a decent group of people.