Simply Booty-ful
The real key to Age of Booty is it's simplicity. It breaks down normal strategy game barriers by reducing the number of things that demand your attention. Your ship is your only active unit to control. You capture towns, but your active control over them is limited to deciding if you want to upgrade their defenses to make them more difficult for your opponents to capture. In controling your ship, you only need to tell it where to sail, and it will automatically attack any targets in range. Upgrading and 'Curse Cards' aside, you play the game almost exclusively with a thumbstick and one button.
Fortunately, this simplicity of UI does not extend to simplicty of strategy. There are constantly choices to be made that will determine your fate. Where do you focus your upgrading resources? Which towns do you target first? How soon do you seek out confrontation with your opponents? Once you start capturing towns, do you focus on upgrading the town defenses or on upgrading your ship? All the while, you also have to react to moves by the opposition to try and hold your own hard-won gains.
All the things that make the game fun and interesting get better as you start adding more human players. Working well as a team is crucial to consistant success, and while the AI is generally competent it doesn't hold a candle to living opposition. The option exists to insert AI opponents into any match, so even those who shy from the competitive nature of going up against another player can get plenty of enjoyment from the game.
In the end, Age of Booty is fun, which is all that really matters.