Can economics that massively favor enslaved labor on early-modern sugar isles be countered to somehow have a white/ light mixed-race majority on at least one?
(No, I'm not racist, to answer the inevitable question.)
Nah, even on Monserrat the Irish indentured servants gained their freedom and became overseerers to actual enslaved people.
The only white majority island in the whole of the Caribbean I believe is St. Bart and that was because it was so dry sugar couldn't grow.
There are those couple islands up further north full of conks but they weren't plantation workers and even then most left for Mainland US when they got the chance.
Redlegs in St Lucia, Barbados, St Vincent, etc.... the descendants of indentureds were notorious in their hatred for labour they perceived as unfit for their whiteness. I mean they were even incestuous until not so long ago because they didn't want to be tainted with black blood.
It's not racist to ask this sort of question I just think its fanciful as a CSA that isn't based on white supremacy.
Caribbean plantation labor and African people lay hand in hand. Europeans had no concept of subtropical agriculture and would die from disease and labour quickly if worked like Africans.