Thanks for the insights and one thing I really enjoy with this forum is that everyone has an opinion. I really knew before I even started this thread that ultimately the answer is - go ride them all and let her decide.....(well, she needs to believe that....)

However there are some lessons here....
1. Does Middle-Weight mean Mid-Capacity? Probably not. So moving to a lower capacity does not assume a lower weight. If you are really looking for lower weight you need to move your focus from Adventure bikes to the Dual-Sport category....and I think this is where manufacturers are going to shift their focus over the next few years.
2. Hence, does the move to a lower capacity mean the bike is more manageable? Probably not? I've heard that the 1200GS is arguably easier to handle offroad than the 850GS just because of where it carries its weight...
3. The size of rider and pillion is critical. I have good friends of mine where both are, lets say, 'generous-of-girth'. Their ideal Adventure bike is very different to mine...
4. What riding are you intending on doing? Typically with a pillion you're doing comfortable tar and/or 'easy' dirt roads and maybe long hours in the saddle. For playing in the technical stuff your focus changes and that's cool.
5. Don't be in a rush. There are a LOT of alternatives on offer...
6. Bottom line is go ride them all - our opinions of the 'best' bike are as varied as the number of bikes on offer. Having different opinions, perspectives and points of view is what makes the Wilddog Forum such a great community....I'm not sure if we'll ever see the unicorn but that just means we keep conversations like this turning and turning.....
7. Maybe Kawasaki is about to unveil another option on 23 November......