Hearty congratulations on your taking the path less travelled. I can see it now... the Provençal version of
Under the Tuscan Sun in the making. Simply delightful.
On your query about the hills and traction, I agree that a good starting place is to get some idea of the actual steepness of the hills
There are at least 3 ways that hill steepness is cited:
Angle (in degrees)
Grade (in percent)
Rise-to-Run (cited as a ratio, e.g., 2:1, 3:1,etc.)
All of these are inter-related, since they all provide information about the relationship between the same 2 sides of a right triangle.
For the most frequently encountered grades, the numbers are:
GRADE /% SLOPE /Angle
6:1 17% 10°
5:1 20% 11°
4:1 25% 14°
3:1 33% 18°
2:1 50% 27°
1:1 100% 45°
You can easily estimate fairly accurately the steepness of your hills with a few simple measurements using nothing more than a yardstick and a spirit level. These measurements can then be converted to the angles in degrees. I tried to paste a figure of a right triangle here to illustrate the calculations, but no luck. You can send me a PM, and I can attach, if you need.
Why do all this? It should assist you in determining if you have the correct (read as safest) tractor for your particular situation. All the loading/chains, etc in the world won't be of much help if the tractor still has too high a center of gravity for the conditions at hand.
The EU has a wealth of heritage and experience in dealing with your conditions. One of the biggest and most experienced tractor manufacturers in the EU is the<font color="green"> SAME DEUTZ-FAHR GROUP </font>. Their URL (in Italian) is:
SDF Group Webpage
There you will find info on the individual brands which the Group umbrellas. A number of them are suited for steep terrain. Another thought to consider long term is adding some terracing. As I am sure you know already, the French and the Italians have done this for centuries to level out otherwise unworkable hills.
Best wishes for much enjoyment in your idyllic adventure. Please do keep us posted, if for nothing other than our vicarious enjoyment of your experiences...