Also, I already finished PotC on the Xbox, but I want to play the mod.
So, my dilema is between PotC build 13, AoP 1.5, AoP Supermod, AoP 2
PotC has lots of quests, build 13 adds more, AoP has only one and it's rubbish. Mind you, once you've finished the quests in PotC, you're left with repeatedly raiding ships and forts and maybe doing the odd cargo run. AoP has just one quest which is rubbish and may as well be ignored; besides that, there are various routine delivery missions, and once you reach higher level and rank, the governor may order you to attack a certain ship or capture a fort.
PotC has a few made-up islands, build 13 adds some more and gives them names of real islands, AoP has accurate islands but no mainland.
AoP has better graphics and more complicated fencing.
So if you're interested in story lines, PotC build 13 will interest you for a limited time, more than original PotC; AoP won't. If you just like sailing around and being a pirate, AoP is probably better.
AoP 1.5 is probably less buggy than Supermod (some of 1.5's fixes never made it into Supermod), but it's still not bug-free.
AOP Supermod opens up some buildings as well as allowing you to walk in the jungle as you can in PotC. AOP 1.5 does not allow you into the jungle at all, some buildings can only be entered if you've captured a colony for yourself and upgraded it, and if you do that, all nations immediately hate you.
I have not yet seen AoP 2, so can not comment on it.