At my dojo Enighet in Malmö, we have made a listing of basic aikido techniques and on what attacks they are reasonably possible to do. The list is long, of course. We have also formulated some basic principles on what to be considered by tori (defender), uke (attacker) or both. In case this is of any use to you, here it all is. There may be additions in the future.
The basics are not all the executable techniques, but a wide selection of them. Aikido contains a number of throwing and pinning techniques, which vary slightly depending on the attack. All cannot be considered basic, but most of them should indeed be.
The system of basics should make compatibility with other aikido systems possible. In regard to how the techniques are done, as well as to what techniques are included, a system of basics should be such that the aikido student is able to train and adapt to the training in another dojo than his or her own.
Basic techniques should be reasonable to perform. Too complicated solutions are not basics. Some techniques are basic against certain attack forms, but not against others where they are very awkward or difficult to do. Furthermore, any basic technique should in itself be reasonably straigthforward.
Attack forms that are not reasonably feasible, are not included in the basics. Some attacks, or combinations of attacks, are so difficult or awkward for the attacker that they are quite unlikely, therefore not to be included in a basic system.
Also other techniques than these basics may be executable and trained. It is important to train more than the basics, to progress well in aikido. Also variations and complicated non-basics should be tried with some frequency. Otherwise the aikido in a dojo risks shrinking to something less than it can be.
Always start with taisabaki, an evasive movement! It is not aikido if not started by avoiding the oncoming attack - even if the attack is a mild or slow one.
Blocking the attack should not be necessary. To block the oncoming force is not really aikido, which should avoid confrontation. Sometimes blocking is practical, but if it is necessary, then the technique needs modification.
Techniques should function to execute. An aikido technique should be possible to perform, and to do it in a way that avoids as well as controls the attacker.
Similar solution for gotai, from static, and jutai, in movement. If a basic technique that works in movement needs to be significantly changed when done from a static start, it should be modified.
Basic training should be done with low postures. The balance and control of low stances is essential to have as standard for basic techniques.
Forces should be united (aiki). In aikido techniques the forces of the attacker and the defender should be joined, and not work against each other.
The need for atemi, strike, should be limited. The aikido techniques should be possible to do with few or no atemi, which otherwise tends to be 'an easy way out'.
Tori’s starting position should be such that uke’s attack is reasonable. The target that uke is supposed to aim for, must be easily reached - not hidden or blocked or otherways awkward for uke.
Tori’s starting position should not be such that only one aikido technique is appropriate. It is no good if tori is positioned ideally for one aikido technique, but awkwardly for other techniques. Tori should stand able to do many different techniques.
Tori should control the situation all through the technique. From the start to the finish, whether it is a pinning or a throw, tori should be in charge and remain aware.
The fundamentals (such as center, ki, posture, etc.) should be stressed in training the basic techniques. The techniques are mere expressions of the fundamentals, and do not work well without them.
It is part of aikido basics to learn correct attacks. Uke is obliged to learn and to do attacks with as much sincerity as with the aikido techniques when being tori. Otherwise, aikido is not learned properly.
Attacks should normally be done with low postures. The balance and control of low stances is essential to have as standard for most basic attack techniques, in order to do them sincerely.
Uke should not intentionally resist the technique. There is no point in resisting a particular technique, thereby being additionally vulnerable to other techniques. Also, resisting somebody who is trying to learn a technique is counter-productive.
Uke should have a continued spirit of attack, through the technique. Uke should remain in an attacker mind all through, keeping an aim at tori.
Uke should not change direction of the attack, during the technique. Uke's initial aim toward tori should remain all through, unless the exercise specifies differently.
The fundamentals (such as center, ki, posture, etc.) should be stressed in training the attacks. The attack techniques are mere expressions of the fundamentals, and do not work well without them.