Yes, occasionally I've added some powdered ginger to my milk/dk choc brew blend. There's also a great ginger syrup from Mountain Rose Herbs that is a good way to spice up a recipe (I use it mostly for my sorbets). If you are looking to combat nausea, I think it will help. I've also used powdered ginger to aid digestion of some dry herbal supplements that I take.
I love ginger but am not a fan of the ginger/chocolate blend so I don't use it in my kava brew often. My goal is to mask the kava taste, so the dark chocolate is the most important additive. No reason ginger can't be mixed with other flavorings if you want- like coconut, pineapple, tea, etc. Actually sounds pretty good