I was tempted to also split the citrus juice to also bring lemon or even pink grapefruit juice into this cocktail but when I made the recipe above it was...
This worked extremely well. As John hinojos comments, the split base really opens space for the citrus. I had run out of lime so went with pink grapefruit and lemon juice, roughly equal, and was very happy with the result. The margarita bitters work a treat to add structure and brilliant lavender and rosemary aromatics.
Brilliant, the combination of both tequilas makes a really great cocktail. For my personal taste it was a tad on the sweet side, so I suggest to be reluctant with the agave syrup.
As it turned out this variant is so far my preferred one. I did play with its basic idea a bit further and add 0,5 cl smoky Mezcal, 0,5 cl Amaro Averna (works always well with citrus fruits and substitutes here the Margarita Bitters) and did replace the agave sirup with Mastiha liqueur (which aromatic profile IMO harmonises well with agave based spirits).
Living in San Diego and on the border with Mexico, we have a lot of different margaritas available.
This was excellent. The combination of the two different tequilas allow the citrus to shine. This is a very refreshing margarita and perfectly balanced. Worth a try.