Little Cayman, Grand Cayman, Barbados, St Kitts, Antigua, etc.. even St Barts if you can stomach the initial tax.
Except Cayman Islands, the other places are plagued with high crime and homicide rates, and they are more expensive than Thailand. Equally corrupt too.
Makes no sense to relocate from Thailand to Barbados to be honest.
Going to Grand Cayman I can understand though.