Hello Fortunate Ones,
As far as choosing Caye Caulker vs San Pedro I think it all depends on what the group is looking for.... Caye Caulker is what I like to call a smaller, more laid back, rustic version of San Pedro and in some cases drinks and dining out can be a little more pricey. I personally do think San Pedro has a way more better dining scene, tons of great restaurant options. Caye Caulker is also known to be where backpackers choose to go instead of San Pedro.
Caye Caulker is not really known to be a party town and everywhere would pretty much quiet down once the sun sets. Koko King's full moon party however has always been a blast and a lot of fun with a good mix of locals and tourists. I am aware that there are even boats that would go over from San Pedro to Caye Caulker for the Full Moon Party. But like I mentioned at the top it all depends on what your group is looking for and what would interest them more. Also,Caye Caulker is just about a 30 minute boat ride away from San Pedro if really wanting to go over for the Full Moon Party there are boats that can be chartered to take you over. If you would be needing any further information please feel free to email me at email@example.com