I just was captured by the phrase of the "correct way", as I was told there is no "correct" way in aikido. There are many variations and you have to choose the best one for the actual situation, you body, the given underground etc.
I wondered if this is true even for a simple 180° turn. I stood up in the pffice and tried, how I do it.
You see usually if you pivot on the balls you are much more stable, as someone told us before. But un standard kamae your heels are in line, your toes are not. So if you just turn on the heels, you are in a correct kamae just in the opposite direction, if you only turn on the balls, you either do not turn enough or your legs are crossed.
So either you adjust feet - if you are allowed to move feet
or you have to switch pivoting from heel to balls and back.
I usually first turn my front foot on the heel, so that front toes are exacts in front of the back foot toes. My body already turns a bit. The I pivot on the balls so that I stand the same way in the opposite direction. In the end I correct again the (new) front foot by turning a little but on the heel. I think this is very stable and practicable, while it is not the only possible solution. And IMHO the major purpose for this exercise is learning to move without your feet being cemented to the soil.
So you might just turn by some 165° (estimated, i.e. not a complete half turn) or by side stepping to adjust crossed legs, etc.
I just guess, purists could face some problems, but maybe I have overseen something, have I?
Kind regards Dirk