lucky lavender - I was also thinking a jumpsuit / trouser suit might add a Bianca jagger-esque twist to affairs (albeit, sadly, I'm not anywhere near as good-looking.)
HermioneWeasley - Yes, I see the need for a jacket or cape of some description.
Thank you all the honest views and tips.
I think I shall go for the first one and accessorise like mad. Possibly with metallics!