for now I'm going to go with SDTEHO, I like CoAS too.
things I like of SDTEHO:
1. better graphics, characters are better made (uniforms, weapons) Tortuga is redone best
2. ships are better (the decks and cabins) also the cannons have to cut the crews down before boarding (opposite in CoAS)
3. better places to visit dungeon and prison, natives, graveyard/crypt. lighthouse keeper
4. floating debris can get you $$ when you find them.
5. the different trinkets and trade items are more than CoAS
6. the EIC building you can go in and get missions from (not in CoAS)
7. drug store you can visit (not in CoAS)
8. the sailing from island to island is more spaced out.
things I don't like bout SDTEHO
1. the start off story quest.
2. the skills of the pirates and other attacking ships soon as you get free-sail
3. the skill boarding actions first starting out is almost impossible to complete unless you've cut down opposing crew with cannon fire. (no hand grenades)
4. rats on board constantly eating your supplies more than CoAS (unless you find a rat god @ the very start)
5. fact is that its on steam
6. the "min crew required" when capturing a ship (after the GoF mod you didn't have to worry bout transferring crew)
7. the log book keeps track of your saves/reloads/health lost
8. the rum is way too expensive @ the start.
those are my 16 things I like and don't like.