If you agreed not to talk much about the past and no divorce talk, I would say treat it as it is, a first date. Do the kinds of things you would have done when you were dating in the first place. Of course with one advantage, you know more about her so you can talk with her about work, friends, tv shows you both watch, etc. Keep it light, upbeat, and fun. Let her see a confident, happy you. Who doesn't like that?
I think there is a lot to be said for trying to contain the "issues" for counseling sessions, be it joint or individual counseling. I know in my case whenever H and I were alone together I brought up our 'issues' and how to 'fix' them and it helped drive H away, because I was not being 'fun' or 'upbeat' in those times. It isn't that you don't have to talk about those things, but like you said, choose a time and place for that. And then spend other times, like your date, just having fun together again.
