Excellent. I agree with R. Spain and like it with Amaro Lucano, which makes it a distinctive Brooklyn variant rather than just a re-proportioned version of Grohusko's original recipe, which I make with Golden Moon's Amer Picon reconstruction. I also like serving it in an old-fashioned glass with a Luxardo cherry for garnish.
The mint notes were one of the first things I noticed on my first sip, but I am also impressed at how much bitterness just 1/4 oz of the Lucano imparts. Good balance overall. I use Cheritelli maraschino, which has a bit more maraschino flavor than Luxardo liqueur and plays well with a Luxardo cherry garnish. By way of contrast, Phil Ward (in the Death & Co. cocktail book) says "no garnish," but the Luxardo cherry works here, esp. with Cheritelli.
Well-balanced; agree that 1/4 oz is enough with thick, bottled ginger syrup. The Aperol ties everything together nicely. And this drink provides yet another use for our jar of candied ginger, which I'm trying to use while it's still soft enough to pierce with a cocktail sword. Distinct and tasty.
Molasses is even harder to work with in cocktails than honey, so thin it 2:1 with hot water to make molasses syrup. I increased the orange liqueur and orgeat slightly and eliminated the sugar syrup in Difford's recipe, then increased the white rum and the lime a bit. No idea where to get Cape Gooseberries. This merits inclusion on your Tiki Bar menu, whatever the garnish.