I just don't get it
I struggle to see how one's character is reflected in one's technique. If this were true, there should be some correlation between ability and character, but I have never seen it. I know 5th kyus that have a more giving, caring personality than 5th Dans and vice versa. Sure - there are some wonderful people teaching aikido. But guess what - there are some wonderful people working on checkout at my local Tesco.
In every measure of character I can think of I can see a complete scatter. I doubt anyone would be able to find a correlation.
Personally, I just don't see how aikido can have a significantly greater influence on character than any other activity. I cannot think of a single person I know well in our dojo or any sister dojos would put 'improving my character' in any top 5 list of reasons to do aikido. Maybe it is just not a British thing...?!