Hi Binkie,
Two fantastic tours to choose between (I took Croatia's Istrian Coast a few years ago and it is beautiful).
At the moment there are 27 travellers booked on the 7th September trip to Croatia's Istrian Coast and 26 travellers booked on the Flavours of Tuscany 29th September departure.
Weather is unpredictable but in Tuscany you can expect highs in the mid-20s and lows in the mid-teens with a chance of rain (so I would make sure you pack a lightweight waterproof jacket just in case).
Kindest regards,
Julia