I wasn't optimistic with dry vermouth and orange juice being together in this.. Lo and behold, I was out of Noilly and subbed in Lillet Blanc... One of the peachiest cocktails I've tried, wow! I did have Bitter Truth Peach Bitters on hand, which arguably faded into the background... Like the suggestions below, a template worthy of experimentation.
Interesting cocktail. Did not have Peach bitters and did not want to use all Angostura, so we opted for part orange bitters and part Angostura bitters. Was a very nice, orange-flavoured with a hint of herbal. Did feel it could use another ingredient - perhaps a little peach brandy or falernum. Haven't decided yet.
So we tried an experiment with the remaining parts of the cocktails we had. Tried both a little peach liqueur and falernum. The peach won. It does change the flavour profile of the drink, but adds a punch.
I used Old Raj Red, Gabriel Boudier Crème de Pêches, and Cinzano 1757.
Would try again with a navy strength gin.