I'm also picky about olive oil. I've heard about countless scams in Italy about fake olive oil on TV. Also to me most commercial olive oils from the South (Italy, Greece, Spain) taste quite mild/soft compared to our olive oil from "Istrska Belica" / "Bianchera" variety.
We make our own olive oil, it is not a commercial endeavour so quality is first above everything else even though this variety is a PITA to grow. It is difficult to prune, more susceptible to various fungal diseases, has a tendency to produce on alternating years but the flavor makes up for those troubles.
Most commercial olive oils use heat extraction, which can also mellow the flavor (in addition to factors like fruit maturity and variety).
We have almost 100 trees of a common variety ("Oblica") that is regarded as very mild, and a few local varieties ("Lastovka", etc) which is usually considered very spicy and flavorful.
But I've made mellow Lastovka oil and sensational Oblica. There are a lot of variables to manage.
We make our own olive oil, it is not a commercial endeavour so quality is first above everything else even though this variety is a PITA to grow. It is difficult to prune, more susceptible to various fungal diseases, has a tendency to produce on alternating years but the flavor makes up for those troubles.