my instructor is a 3rd dan aikikai who got his 3rd dan after more than 10 years which I guess is quite some time in aikikai and he was some kind of a "street" person so he tends to get into some fights. but 95% at the time he was teaching class, he always teaches henka waza. I have no problem in learning something new, but the problem is when I think some of his henka waza isn't effective. I know this because I have been the one he used as uke most of the time. when he's doing the technique, there's an opening for a punch or a kick or elbow strike which doesn't occur as much in kihon waza (that's why I like kihon waza and repect O Sensei so much for his research on human body). in some other times, I deliberately loosen my grip so that he doesn't look bad when performing a technique.
From your post it seems that you know better than your sensei. Why not start a dojo of your own?