Good international travel destinations from mid-January through mid-March

Hello. I'm looking for suggestions for good travel destinations beginning from mid-January and returning by mid-March 2017. My wife and I wish to travel for about 3 weeks during that interval. We are looking for suggestions for destinations which have some optimal feature or features at this time of year. We also wish to avoid negative surprises due to cultural or climate factors. We have no particular restrictions on destinations world-wide, other than South America and Australia which we have recently toured. But even these are not entirely off the table, just lower priority. We are US citizens (i.e. this could make some destinations inadvisable). Suggestions as to good tour operators for a destination would also be appreciated. Thanks for any input.