Thanks girls Yeah, we're definitely looking for something as pale as pale can be, DD1 is hyper enough without trying to get her to sleep in a fuchsia-coloured room! And DD2 is easily overstimulated so definitely baby, baby pastels for her room
Sticking to white and pink for the walls, then just adding little splashes of the additional colour using carpets/rugs (we're replacing the carpets *sometime* soon, I hope!), wall hangings and stuff like that, to keep costs down (great tip, Muppity!).

DD1 is all into butterflies atm too, I'm thinking maybe purple or a powder blue and going from there?