Thanks all for the comments. I think boots are slightly ahead but sandals also featuring strongly. I have read and appreciate all the feedback and it was also timely to read Angie's blog. I quite like not having a gap between the boots and the dress...but I can see how some people prefer a small gap.
I like the idea of big hoop earrings and a bangle stack (or cuff). I would be happy to get new sandals and also have some cream lower wedges and some almost nude sandals. As the occasion gets closer I can see what the weather is doing - if we get a warm night the boots might just feel wrong. I think cognac or nude might be the best colours- if I wear the black ones I would wear something black elsewhere.
I did not mean to post and run - we ended up having a big day in the garden and working down at the athletics club, with family also visiting. So I didn't quite get back to the forum.
A couple of comments:
Deborah - I think pants would annoy me under the dress, while not too clingy or thin I would get lines around the midsection and I like the smooth line of a slip or shapewear.
Isabel - I know what you mean. At home I would not usually wear knee high boots either, they are streetwear.