Thanks. Looking at them with slightly fresh eyes, I think we've discounted Eleanor, Maria, Kate (damn that wedding) and Isobel (two friends with them in the last few weeks).
Edith would be Edie. I also quite like Helena, but pronounced Helen-a, rather than Hel-a-na and I'm not sure I can be arsed to go for a name that has two common pronunciations.
I love Thea and I'm working on DH a bit I think, but feel it should be lengthier. I wanted Alethea, but he says no, but is prepared to contemplate Dorothea, which could be quite nice. Anthea is a pretty name in itself but has Turner connotations of course.