Sooo...one of my fav yarns at the moment is the lovely 8ply pure cotton from Bendigo Woollen Mills, it is lovely to use and has a nice drape to it. I know it's nothing fancy, but so useful and soft, my only problem is the colour choices are a bit limiting, nothing too bright and there are a few shades that are definitely a little nana-ish.
Having said that, there are still some nice colours to choose from, and I am always on the look out for bright colours in pure cotton that is 8ply, sometimes I buy two balls of 4ply and use them together, which works ok.
I also really like Colorworks 8ply merino wool, it is really soft and pleasant to use and has some great colours! (Colour is often a first requirement for me in my yarn choosing!!) I am happy when I have a nice little stash of Colorworks, because it is often my 'go to' yarn, so I try to keep a few balls of my fav colours on hand most of the time. ( Unfortunately they have just discontinued my fav green, so am stockpiling this colour when I come across it in the shops)
I don't really like using acrylic yarns as I find my hands get clammy and hot and then knitting and crochet are no fun at all!!