Hello from a back garden in England.
Having read this thread with great interest, I wonder if any of you are familiar with a variety of yeasts called Kveik? Kveik yeasts are Scandinavian farmhouse varieties that ferment extremely quickly and produce their own, commonly fruity or citrus, flavours. Usually, such yeasts are passed hand-to-hand between farmhouse brewers, but recently they have become available commercially.
Inspired by this thread, I've carried out a number of experiments using the few dozen Virginia, Burley and Havana plants I now grow each year (started as a lockdown hobby), resulting in a tobacco blend with the kind of dark fruit scents found in Schmalzler nasal snuffs. Such scents persist as the resulting tobacco ages and offer a means of introducing flavourings without having to add toppings that affect the smoke. Furthermore, a typical kveik fermentation completes in days rather than weeks.
Should you be able to access these yeasts, I would recommend trying them as a way to carrying these experiments further.