The extremely brief ones I can answer for. I wrote the single line entries just so they weren't totally empty. I can't say how detailed we should be, but there should be an upper limit on the detail, since they are only meant to refresh peoples memories. I, as evidenced by my poor quality, don't really have any right to say tho, so you should wait for other people's opinions.
EDIT: as always, the answer is probably just to do what you want, and people can/will edit and change things until we're happy. So there's no real reason you should wait for input, as long as you're happy for people to change your stuff.