IMHO I think some of hte most dangerous aspects of aikido are related to techniques but in and of themselves not part of techniques
- catching foot in hakama
- catching fingers in gi
- crashing into other practioners at seminars
- crashing into objects
All of these (save the foot in hakama) can be greatly mitigated by the skill level of the aikidoka. An experienced and careful nage will not put uke into harms way at a seminar or throw uke into objects, while an experienced aikidoka as uke will see things coming and adjust accordingly. That said, it doesn't always work and accidents do happen, however seemingly less so as the experience and skill grows.