Hmm... my curiosity knows no bounds.
Coming from an Aikikai background, I find it fascinating that you are all discussing intently on the subject of katas. Does kata make up a significant part of yoshinkan/shodokan/similar style of aikido's curiculum?
Our method for learning the techniques basically has the sensei demonstrating what he wants us to practice. These techniques are done with omote and ura variations. Sometimes, additional variations are emphasised, such as a different tenkan, uchi, soto approach, atemis, reversals and such. With the limitless adaptions this type of training has, it becomes I suppose daunting for the average beginner. Personally I had problems with the omote and ura variations when I first joined.
Although the katas that you've mentioned seem to me a bit limiting on Aikido's open ended techniques. I find it a as a very smart system to introduce beginners to the art. as well as keeping the seniors from not practising their not so favourite moves, which you will find most would do when left to their own devices (I hate hammi handachi for instance
What are your thoughts on this? Also, what kind of turnover do you have with beginners? For us, quite a number of beginners disappear after several mind boggling lessons. Or possibly from aching bodies as a result of learning ukemi's the natural way.