Tried to replace the simple syrup with rosolio di bergamotto. Smells great, tastes great.

Tried with anejo and equal parts of campari+grand marnier. Works well.

I tried almost the same combination: four roses small batch select (adjusted to 40ml)+cointreau+Antica di Torino+lemon juice+a bar spoon of syrup from my maraschino cherry jar. Characters of the four roses vividly expressed, with refreshing citrus and warm spice notes. Awesome bedtime sipper, but I'll try with Grand Marnier+lime juice to see whether it gets even more enchanting.