Re: Aikido against very high kicking (like in tae kwon do)
My first dojo taught techniques against kicking about 1 class per month. It was almost always against front-kicks, though the instructors would practice against some more advanced kicks.
Unfortunately, it is one of those areas where your ukes must be a little more athletic. If you are defending against a kick from someone who has never, and would never, throw one, then it kind of feels like defending against a leg sweep instead.