f you would not mind, I would like to give you some ideas and suggestions myself.
Just as a first note, Tia Dalma's shack is NOT on Pelegastos, it is on Cuba (According to POTC canon)
http://pirates.wikia.com/wiki/Tia_Dalma's_shack
Perhaps following COTBP, this could happen
1: On your way back from Port Royal following COTBP, you encounter a pirate ship captained by Cap'n Roger, who challenges you to a game of cards saying that if you loose, you must give him your title of pirate lord and you win. His voodoo witch doctor first mate then turns him and his crew into skeletons after Roger kills him out of frustration. Roger, now a skeleton, vows to take Revenge on you as he thought you cheated him at cards and his mortality
2: Sail to Tortuga and meet Teague
3: Teague tells you that the EITC are becoming a pain in the rear and tells you that you must gather allies for the inevitable war to come, he sends you with a letter to the buccaneer camp on Hispaniola to meet with Garcia Avarica, the Spanish Privateer Governor and sends Captain Bo Beck to help
4: After rallying Garcia to the cause, sail to Petit Tebac to meet with French Privateer Governor, Pierre Le Porc
5: When you arrive in port, Pierre has British soldiers (whom he told of your whereabouts) arrest you and take you to a prison on an uncharted and secret location only known by the navy
6: In Prison, you meet the notorious Blackbeard and the smuggler Richard "Rex" Fallon who help you devise a plan to escape
7: After making out of prison and onto the small island, you instruct Rex and Blackbeard to make their ways to your getaway ship captained by Bo Beck and you yourself get discreetly picked up by Teague's ship
8: You sail to Port Royal with Teague (who drops you off and leaves) and he gives you instructions to rally with Tia Dalma in the town square
9: Tia Dalma tells you to go to Tortuga and rally the pirate Lords for the coming war as well as to go to the Port Royal fort where Capitane Chevalle is to be hanged and free him
10: Go to Tavern to find Will Turner and fight thugs
11: Go to Blacksmith and find Will Turner
12: Go to Fort Charles and cause a diversion in order to free Chevalle, then fight the soldiers
13: Escape Fort Charles and instruct Will Turner to hide out in wherehouse and strike a deal with local smugglers to take you to Tortuga
14: Meet Smugglers at Port and go to Tortuga
15: Go to Faithful Bride and talk to Gibbs, Rex, and Blackbeard who tell you that the Pearl has been seized by the navy and instruct and after you offend Blackbeard, Rex is told to rally your crew for you and go after the Pearl
16: Go to Brothel and fight thugs and duel Villenouva who (if you beat him) and Mistress Ching decide to go to Shipwreck Cove and meet Chevalle who is already there
17: Visit Annamaria in port and ask her if she needs a first mate and she lets you sail on her ketch with her to go to Havana
18: Convince Sumphagee to go to Shipwreck Cove
19: Sail to Martinique and convince Ammand to go to Shipwreck City
20: You and Annamaria wash up on a desrted shore with another crewmember after a severe storm and you try to find civilization
21: You find Jocard being held hostage by Bartholomeu Roberts' ghost and you fight it to save him
22: Find a Tartane and sail with Annamaria, Jocard, and the other crewmember to Tortuga and you convince Jocard to go to Shipwreck City
23: Rex returns the Pearl to you in the port after succesfuly retaking it from the navy
24: Sail around for a month and an attack by Roger's flagship initiates which you must board
25: Board Roger's ship and kill him
26: You encounter the Dauntless captained by Norrington which you have to engage during a storm
27: You have a dream about Davy Jones after Rex encountered the Flying Dutchman after beating Norrington
28: Sail to Conception
29: Instruct Gibbs to have the Pearl follow the prison ship you are planning to board
30: Impersonate a Portuguese soldier and sneak aboard the prison ship
31: Switch places with prisoner who you tell to join your crew and go over to Pearl
32: Portuguese prison ship automatically takes you to Turkish Prison where you are jailed
33: Busted out by Teague who instructs you to free the other prisoners
34: Fight Warden who has the drawing of the key on him
35: Escape to cliffs with prisoners and Teague
36: Teague and prisoners rush to Teague's own ship and you sneak into a coffin shortly before the thug guards come back (they throw you in the coffin over the side of the cliff)
Dead Man's Chest Begins