Me too, I use to call characters with their more used name, first reason it is because usually, especially with large casts, I start remembering names only after reading them in the forum, take
K as example, I still have problems
. Except when I don't like how it sound (a bit differently from Kanon). So, since
Kazuto doesn't sound good in my language, no matter if people use it or not I would not use it.
On the other hand, even if I really like a character I don't care if a name / surname / nick sound better or not.
The best example is
Inaba, her name is
Himeko that could be easily shortened into
Hime, a very befitting nick for her, it's even short and cute, but I prefer
Inaba /
inaban /
dereban, because I'm more accustomed to.
Lastly, it's even because I'm sure people don't get me wrong while I'm writing about this or that character.