I would change on thing at a time. It makes wonder about your choice of frame. For my road bikes, I've used 100 or 110mm length, -6 or -17 stems and no spacers to get an 8-10cm drop from the saddle to the top of the bars. 10 degrees is a lot of rise. Try 10mm longer at a time, without increasing the rise. Too much length causes an uncomfortable arm angle. Try flipping that 10 degree stem to -10.