We go to Roatan every year for the last 5 or so. Just got back. Latest we've been is October, but friends live there and other friends go for the Christmas week. We have always stayed at Cocolobo, 5 minutes walk from West End. We now have a partial ownership of a rental unit ("garden cottage") there. My wife and kids spent all of July there. Obviously we really like it there, so this is a little biased! The water temps are pretty steady 78-83. December is going to be closer to 78. The water temp at the surface is the same at 100'. I dive in a rash guard and then add a 2mm vest for 3rd dive or night dive. The boat ride back is the coldest part, but they are generally only 5-10 minutes.
The sand flies bite, but you don't necessarily know until they start itching!!
Food and diving options are plentiful in West End. Our preference is Sun Divers, but there are very good alternatives all within a short walk.
We fly AA, and due to past issues in Miami we try to fly via Atlanta or DFW. Due to the Boeing 800 max issues our return flights this year were changed a month from travel dates and were going to require an overnight in either DFW or Atlanta with no 'help' from AA. With 4/5 kids with us that was not good, so we opted to fly return through Miami. Thankfully they have done a lot of work to immigration and customs (mostly kiosks now) and have importantly, to me, changed it so that permanent residents (me) can go through with citizens (family). That was not the case previously and caused a lot of extra time, headaches, frustration, missed connections etc. etc.
When flying into RTB, get seats in rows 25-28 (of 30 or so) if you can't get near the front. They open up the rear doors so you actually get off much quicker, and as the lines can be long once you're in the building this can make a big difference. Left side of the plane (looking forward) will give you views of the island as you approach.
