Art school colouring the lines

I tried a few different ways of colouring the lines on this as I'm still trying to push how I do it, especially as when I first started colouring my lines I would just use a slightly darker colour and I don't think that's bold enough. I did mostly stick to this but I really tried experimenting where I could. I also made the lines on the rock rather dark against the paler rock and really light lines on the dark ones, this will make them stand out a bit and will hopefully work with the different tones of the rocks to create a bit of depth.

I did think that the pale lines on the pink really doesn't work as it makes you question what it is, when it's already a bit vague. 

With this as well the pale doesn't show up next the already pale pink, even next to the green.