I just installed MyCelium and I had to write down 12 words otherwise I cant continue. Im sure that it is a very good and secure wallet my not feasible for a 15 minutes pitch in a taxi. Does no 20-30 seconds set up wallet exists? Maybe that would be a nice business idea
I believe that's also how it works in Breadwallet (iOS): it notifies you of the possibility (and urgency) to create a one-time backup, but you can still continue without doing so.