I used a MU Namor as the base and a Thor head, with some generic pirate figure accessories, sword, belt, hat and jacket.
I recently re-played Monkey Island 1 and 2 on the ipad, the first thing Guybrush says is that he wants to be "A Mighty Pirate". This is my interpretation of how Guybrush would look, should he have become a mighty pirate.
I went with an Indiana Jones meets Kraven the Hunter for the look.
I also made a Pirate's hideout for my kids too, the island fortress was made using parts from a chap mei pirate ship, newspaper and plaster. The "eyes" are cannons, with spring loaded projectiles, and there is a secret door in the cliff face, as well as a working winch/elevator inside for transporting people and cargo, as well as a prison on the rooftop.
Yes, that is the figure, standing atop the mountain, next to the flag.