This forum is a great resource!
Some thoughts:
*A plant living (high) in the mountains of Italy or Iran may well have freezing winter temps and chilly summer nights. But (I presume) a long, relatively hot and dry summer with plenty of sunlight. While e.g. -15 degrees celcius might be tolerated there, this value may or may not be what limits how far up north the plant will succeed along the coast, where low temps are moderated by the proximity to water mass, but so is summer heat and sunlight is limited.
*Plant survival and (worthwhile) fruiting quality and quantity may not be perfectly correlated. Some species may be prone to being killed in winter but otherwise put up good fruit in numbers, while others might grow healthy but never be able to set good fruit. The former may be suited for heavy winter protection or lugging pots inside, while the latter may need a green house.
I do wonder how I can improve micro climate, and what can be gained from this. Well-drained soil is needed by most plants in my (humid) climate. This means more rapid heat up in spring, but more frequent watering. Planting against a reflective south wall/fence of some heat retention seems like a good idea. Using black woven ground cover. Using large stones for heat retention and weed protection. The next step probably is a green house of some sort, or plastic for wind shade.
Mt Etna type figs seems more prevalent in the US than in europe?
This page describes a thorough study to find figs suited for Denmark:
http://www.westergaards.dk/node/182
This page describes one mans attempts at growing figs in Sweden:
http://www.fruitiers-rares.info/articles57a62/article59-Fig-growing-in-Sweden-Ficus-carica.html
K