I prefer the first choice because our flights are so long that two full days are lost to travel.

With a two week jaunt, that gives me 12 whole days to play and chill and truly relax.
With two one week jaunts (14 days) there would be 4 days lost to travel and only ten days to play.

Savings on airfare can go towards upgrading to a really great place to stay, or even a shorty trip closer to home for an emergency getaway.

Out first trip to Negril was for 14 days, so we had 12 to chill. It was perfect for our first visit, and like you, we changed rooms midway.

Any tropical getaway is nice though, so I would take either one.

Happy planning.