my personal opinion is that after the war, his view of fighting changed, especially when witness the aftermath of the two nuclear bombs. as i grew up in a rather vicious war, i can assure you that when you were on the receiving end of a B-52 bombing run, you would desperately want peace. maybe he saw that aikido could be a vehicle for fighting, not against others, but against oneself and to transform oneself to be a better human being. that's my opinion which might be completely off the track.
as for training, we can use the 80/20 rules. we won't be able to satisfy the 20 percent of the outer fringes where folks either wanted extreme realism to their training (which they can find it in other venues) or the taichee health conscious. so if we can define the curriculum that hold the 80 percent folks who are not at either extreme ends. one of the key for good training is to expose folks to other practices, be it other aikido dojos or other arts. you might lose folks, but if you are confident enough with your aikido, then your folks would recognize it and learn better. in my organization, ASU, we are encourage to try other stuffs as the leaders in the organization demonstrated by example.
I agree with the first paragraph.
On the second I would say 80% want want health and wellness and peace, both inner and outer. Far from extreme I would think.