Okay, finally got around to making the spikes and tested how they work/look on a scrap piece of pleather. Turns out that, not only are the spikes a pain to make so many of, but they don't stay stuck on very well since the base is so small. They are also a little too pointy to be a good idea for a plushie since not all of us are BAMFs like Roxanne and willing to impale ourselves for a hug. Instead I have decided to use metallic fabric paint. It makes short, but soft spikes, which work perfectly for cuddling.
The big spike is the clay one and the others are all the metallic fabric paint. They're knida rubbery, but it works perfectly for this. No stabby bits.