I'm honestly not sure that we do need a female Doctor. I understand and agree with all the arguments in favour of it... but it has to be done at the expense of a non-violent, intellectual male role model that is suitable for all ages, and we are also in pretty dire need of those so having fewer is not an ideal thing. My favoured solution would be to re-introduce Romana (or at least a similar character) and make her the character she should have been without 1970s BBC sensibilities getting in the way. Turn the dynamic of Doctor Plus One into an actual duo. Which would have the added bonus of teaching equality.