Doing Japanese this year. Not sure if mine is entirely standard but I hope I can be of some help
My introduction is basically the same as yours, with the exception that I didn't mention what the sources talked about as that could form one (or several) of the questions in discussion, eg. "What did you learn from the book/Internet/interview?" In my Chinese exam last year they asked about one of the books I read, so yes they do ask about the contents of sources... at least in CSL they did. I'm not sure about other LOTEs, but better safe than sorry, right?
Other general questions might include "Why did you choose this topic?", "What was the most interesting thing about this topic?" etc. I also prepared some extra information about the broader theme - I'm doing "Valentine's Day and White Day in Japan", but I also wrote a paragraph on other traditional and contemporary celebrations in case they bring it up ("Are there any other Western events celebrated in Japan?")
For my DS I structured it into four sections (Valentine's Day, White Day, good points, bad points) and then wrote questions underneath each section, starting rather generally then becoming more specific. For example under the "Valentine's Day" section I have questions such as: what is it, how did it begin both overseas and in Japan, how it is celebrated in Japan, how are the customs different to Australian ones, what kinds of gifts are given, how much do the gifts cost, are they hand-made... etc. Many of the questions/answers partially overlap, but basically my goal was to include most (if possible, all) of the questions they might ask.
If you have a native speaker friend/family member/teacher, it would be a good idea to practise with them and ask them to brainstorm all the questions they can think of about your topic. I practised with our student teacher and we went from Valentine's Day chocolates to the complexity of Japanese social relationships heh
My DS is about ten pages too, but I think the number of pages is really just an arbitrary factor; it depends entirely on whether you, yourself, feel prepared, whether it's with five pages or twenty.
Anyway just my two cents but I hope it helps... Good luck!!