I've been researching this topic for a while.
For the greatest maple flavor I'd recommend using the a Grade A Very Dark, Strong Flavor, not the Grade A Golden, which is used to make pancake syrup. Connoisseurs prefer the taste of the first grade.
The dark, strong syrup is sometimes compared to molasses, which is fermented then distilled (or not) nto rum, and is often used in baking, as in molasses cookies. Undistilled might be more like a mead. Someone ought to experiment with a maple syrup rum. Molasses fermentation for rum has it's own specialized yeasts.
Just some thoughts.
BTW, all grades of syrup has about 67-69% sugar, if that helps. The ratio of glucose to fructose and sucrose varies some, but not much.
Most experimenters seem to suggest that the longer it ferments the better, a minimum of two years, perhaps as much as five, for technical reasons I don't understand. I'm not a home brewer.
I started this journey to maybe realize the maple mead in Lois Major Bujold's SF novel, A Civil Campaign. She describes it as rough and an acquired taste. Perhaps the Barrayarans don't know of the problems with wild yeasts.