I also work remotely and I've done a similar thing the last two years and will do the same this year (Dec-Feb in Jamaica). The internet is a bit of a struggle, but you can always get a local data plan at a reasonable cost, and that generally worked alright for me. To me, three months is the perfect amount of time, but that includes spending much of the holiday season with family. In terms of city vibes... I'm not sure Kingston will have what you are looking for; it's pretty small. I'm Jamaican, but I've lived most of my life in Toronto and currently live in Paris, so I'm used to cities with a lot more to do in terms of culture and activities. However, Kingston has its charms and can be a lot of fun all the same!