Hair Dye Answers

I really have an urge to go blue-black, because I’ve just always loved that color. My natural color is an ashy, desaturated light brown, but I’ve dyed it a dark brown twice over the past six months or so. (Herbal Essences ‘Foxy Brown’) It looks good dark, but I’m a little apprehensive about going to the extreme. I have blue-green eyes that tend to change to straight blue. My skin is pretty pale on my face, but still warm. Also, my hair is pretty thin/fine – I have to use volumizing shampoos & a round brush, blow dry upside-down, all that. Would I be at risk of showing my scalp too much if I went darker? It wasn’t a problem with the dark brown, but I don’t want it to become a problem with blue-black.
Thanks!

I dyed my hair black back in December of 2007, & I want to dye it blue-black with Raw Demi-permanent dye from Hot Topic. I know if I dye my hair blue-black with it already being black I won’t be able to see the blue in it. I really don’t want to be a blonde for a long period of time. So how long should I wait between bleaching & then dying it again?

Well, I used Garnier 100% Blue Black on my typical Asian-shade hair, & it came out pretty black (which is good, since I’m still schooling), but I want to make the colour darker & darker gradually.
Do you think it’s possible to just mix the dye & developer together & dump it in my conditioner, & then the dye will keep ‘dyeing’ my hair as I condition my hair at the same time?
I think it sounds pretty feasible, do you think it could work?
Also, why?