My preferred length depends on the thickness of the leather. I have a 3mm thick strap that is a 160/90, it has a good tail and the buckle sits very comfortably just where I want it to. However, I have the same lengths in a 5mm and although the tail appears slightly shorter, the main problem is the buckle, I just can't get it to sit right, just a bit too short.
You live and learn and that's where the fun is.
