First of all, I think it is hilarious that EC was chosen as the "low magic" island. I mean, it was always the home of Sirion - land of elves. I don't know if any of those grandfathered elven characters still exist but it is still funny to me.
Secondly, I always recalled BM as being described as a "low-fantasy middle-ages world." At least that's what it says on the home page. If that really is the case then I would suggest bringing the power and frequency of magic down to a bare minimum on every island. Make magical events rare enough to be considered legendary events. If not, consider updating the home page :-)
If there is still a need for an island with lower levels of magic, then I would aim for BM = low-magic with one no-magic island.
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