Would be interesting to hear what you did/how things are going!
My thoughts/experience:
OHS - Years ago I had a nightmare there with my son in the pre-prep department. Zero pastoral care. Zero parent sympathy or empathy even. Very poor and high-handed management of staff and parents. Dreadful all round. It is supposed to be better now, though.
OHS is the only school of the three that I know of where several parents have taken their children out because they were unhappy with the lack of genuine pastoral care, and the way parents were dealt with. It is a little bit like the Emperor's new clothes there. You assume it must be marvellous, and everyone acts as if it is, but when you look closely at what is being done, it doesn't bear too much scrutiny. And in the lower school the respect for parents really leaves something to be desired.
Rye - you're right - it sort of doesn't seem to feature. It is the place about which people always say 'it's very nurturing'. It has the best setting - sweet and secluded, with lovely grounds. The staff are very nice to deal with. It is slightly in its own little world. I suspect it could be very nice at lower years, but from 11 really tends to be for those who need less pressure/more support, I think.
Headington - seems to me the best of all. Have only ever heard great things about it. Nobody seems to have anything bad to say about it. Girls just bounce along the corridors with happiness. It manages to feel both focused and relaxed at the same time. I imagine girls come out of there with a very positive outlook re: both themselves and the world.