The duration of the responses will be increased to 9 minutes on the next release. We have received feedback from some of the mentors on this and have observed some mentors sending more than one response to 1 question. That said, the experience is meant convert into as a dialogue, which it often does.
Customized talks for cohorts os users is an excellent idea. What type of talks would you like to see, just out of curiosity? Pre-recorded, customized sessions, and live videos with groups that can send in questions have been discussed.