Oooh... lots of questions!
Ok... here goes: lol
Kisska ---- I would wait at least 2-3 weeks after a perm before you color. I know most salons will do it almost right after if you want them to, but honestly for the sake of your color and your hair... try to wait. Ironing hair will not normally affect color or perms as long as you aren't using a chemical relaxer or straightener.
Liltweekstar --- Usually those color depositing shampoos are good to give color a little kick and add more shine/vibrance. I don't think you'll see much of a result by using a lighter color on darker hair. If anything you might see some red or golden tones in the sun... but as an overall change, it usually isn't much.
Jessiemau ---- You can mix both product lines... and create your own routine just for your hairtype. I find that if you use the Healthy Sexy shampoo and conditioner, and then use a Big Sexy root lifter or hairspray... that you can keep the moisture that you need yet create the styles that you want. Just have to experiment to find what works for you
Kwitter ---- Thanks Kel!
Actually thicker hair works better on cuts like this because you won't have to go crazy with product to get that height in the back. Thicker hair usually helps out a lot with keeping the volume. You just have to have it stacked with the shorter layers in the back --- usually your stylist can judge by your facial shape how high to go with it --- but I think you could pull it off nicely!
Yesterday_x3 ---- You could do a semi-perm on the roots... your colorist shouldn't have a problem working with it. Actually the semi's are great for root touch ups because they will blend in the root color to the existing haircolor and not totally change the result. Fading to a translucent stain just usually means that the color will oxidize over time... and become more blended with the current color. It's hard to explain... but it will usually look less "stark" and more natural. Think of it almost l like a lipgloss vs. a lip stain. A gloss usually coats, while a stain adds color, but not really any texture... it penetrates.
HTH!