First solo trip!

Hi everyone! I’m working on booking my first solo trip (31F) to the Caribbean in October. I’m an experienced traveler just haven’t really done anything fully solo before. I’m looking at either Grenada or Sint Maarten and would love some feedback! Mostly I’m wanting to relax. I am an introvert with an extroverted job so I’m looking for space to relax/turn off rather than go out and meet a bunch of new people and socialize. I love nature so I would love to do some hiking/visit wildlife reserves and maybe do some kayaking or snorkeling. I’d love to hear your thoughts on if Grenada or Sint Maarten would be best for what I’m looking for. Thanks!