had to repeat this for truth and accuracy - a lot of the big ukemis I've seen from many techniques in aikido are "Whee-this-is fun" led happy ukemi rather than necessary.
This is one of the reasons (among others) I was told we don't do breakfalls in Seidokan. And practicing that way changes the dynamics quite a bit of certain things and means you have to get very good about kuzushi, range, etc. to maintain control with techniques like kotegaeshi and shihonage. Just fwiw.