Aircon
I tour around France quite a bit in my 2001 Robin Regent. At 25C+ it does get uncomfortably hot in the cockpit.
My latest model does have improved ventilation but still not that good.
I have discussed airconditioning as a retrofit with Robin - they tell me that there are packs available for the 0360. THe downside is certification and - they tell me - 13kg for the entire fit.
Also - take out your wallet and repeat after me - 'help yourself'.
So - in theory it is possible but in practise not.
This is why the French clubs seem to be at their most active in the late afternoon/ evenings.
On another note - how puzzling is it to see aircraft shut up tight out in the blazing sun without even so much as a canopy cover or sun shield to protect the avionics.
I have seen some incredible examples of faded paint, cracked upholstery, melted headsets etc. It must play havoc with the avionics too. I bet the temperatures inside will be really really high.
I carry a full set of Cambrai touring covers with me.
It is surely a false economy not to cover your bird up in the sun.