Precisely, as the Girls of Great-Britain and Ireland Tiara is so much Her Majesty's "trademark", I would have hoped for another tiara, and the Oriental circlet would have been a very good choice, in my opinion, to complement Queen Victoria's ruby parure.
Queen Elizabeth II has worn the Oriental circlet only once (see pictures below) - which is a pity, because it suited her very well, and I find this tiara really lovely (the Girls' Tiara is very pretty too, but it is so often seen that I find it a bit boring...).
And considering the Queen's white hair and white dress, I think that coloured jewels would suit the Queen better than "white" (i.e. diamond and/or pearl) jewels.