What's in a name? sensei, shihan, etc.
Particularly in aikido, I've increasingly noticed that when trying to speak to a teacher with respect, one may refer to him or her as "shihan" (or, "soke," "shinan," "shisho", to give a few more examples). It occurs in Japan, too, and some teachers seem to expect it. But it's not really correct.
Shihan is a license, a diploma, more than a term of address. One doesn't get, on the other hand, a "sensei license." Calling someone shihan would be somewhat like calling your university professor, "diplomate emeritus."
One thing that people may not get is that within the formality of the dojo, there is also, hopefully, some ease. Referring to one's instructor by an awkward locution would make things "stiff," if not odd. And those teachers who expect or demand it, therefore, tend to create a brittle, rigid relationship with their students.
So I'd recommend the use of the term "sensei" - it gives respect, but defines you, within the context of the relationship you have with your instructor, as having your own integrity. As most surely know, sensei means "lived before" - implicit in that is "I intend to catch up to you."
BTW - Kancho (like Shioda Gozo) or Dojocho (like lots of people) is a common term - kind of "formal/informal" - sort of like "boss"