I don't really have much of a tip about picking up for a neckline except to say that it's easy to pull out what you've done if you don't like it. Over time you'll develop a feel for whether or not you need to pick up a half or a whole stitch over from your last one. The video that salmonmac suggested is one that I rewatch whenever I'm about to do a neckline.
I am a little bit of an expert on hard-to-see yarns because I knit lots of baggy black sweaters, so I think I can help you with that.
The fluffyness of your yarn is good because it can help hide any holes that can sometimes happen when picking up stitches. The way I'm currently dealing with hard-to-see stitches is a clip-on book light
. I bought it to use when I can't sleep and don't want to wake Mr. Rie. I use it all the time now when knitting, especially as it's portable. It's a cheapie little LED with a bulb smaller than my pinkie nail. I have even clamped it onto my wristwatch and curved the long neck toward my knitting. They even sell them at drugstores. Seriously, save your eyes and use an extra spotlight.
However, if you have the means, there are companies that make much better lights
specifically designed for crafting. I'm not advocating any brands here, these are the first two that came up when I searched for examples for you.