If you, like me, can't get tobacco liqueur in your area for the Louisville Sour, I'd suggest the 100 Year Old Cigar; robust and reminiscent of it's namesake.
An atomizer really is a game changer for these types of cocktails. I've always used an atomizer for absinthe because I can't stand to waste it, but it's obviously even more valuable for Chartreuse. I keep atomizers of absinthe, Chartreuse, Angostura, and Laphroaig on hand. Practical but also always very cool for your guests!
My brother and I were just talking about this drink the other day. He said it would be cool if a bar took drinks from the 70's and 80's that were considered bad by todays standards and modified them. I brought up how NoMad did this with a few drinks including the Amaretto sour. Haven't had one in a while, I guess this is my sign.
One of my all time favorite Old Fashioned riffs. Agave spirits are not usually my favorite, but in this application they shine. I also enjoy this with orange bitters, either instead of the chocolate or in addition to it.