Tried this tonight with ABA Pisco (Alexandria / Muscat grape). I quite enjoyed this as a change from the usual gin based Last Word. While I didn't find it too sweet, I agree with Florian that maybe a little more Pisco relative to Luxardo might by bringing out more Pisco elevate the cocktail. Still for me though, a solid 5.
Now I retried this good cocktail with the original proportions and Pisco acholado (thx Peter). In my opinion like this it is a slight bit too sweet, Luxardo is overly dominant and the Pisco character vanishes. So I suggest a try with 4cl Pisco, 2cl Chartreuse, 1,5cl Luxardo and 2,25cl lime juice. Anyway I would keep the additional dilution.
My rating in brackets, because I only had a bit maraschino left. But I balanced it with simple syrup and although it was only ¼ Luxardo of the recipes amount it was clearly detectable.
Dear Andy (and Pekka), please try this cocktail with Achlolado rather than Mosto verde and you may find it less sweet and more to your liking (I’ve just done a head to head)