I think Antigua is a good next step after the BVIs. You can circumnavigate the island and pretty much always find a protected bay/anchorage regardless of which side you are on. Not as crowded as the BVIs and not catering as much to charterers, but still enough infrastructure to provide plenty of options. Also, a crossing to Barbuda where you can have a miles long sand beach to yourself is a great experience - though if the developments on the southern end of the island continue to creep north it might not be like that much longer.
If you have at least a couple of weeks, a one-way from Antigua to St. Martin (or vice-versa) is a fun way to broaden your experience without having to push your limits too much.
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