This tree needs about 2-3 more years of being left alone to grow. This spruce is at the bare minimum foliage for survival. If the soil is draining well, I would leave it in this pot for a couple of years. Your other option would be to gently lift the tree from the pot and plant it in a bigger container with a good conifer soil mix. In about 2-3 years, you can decide on some light styling options. I know that being told that you should not work on your tree for 2 -3 years is not something many people want to hear. However, it will pay off in the long run.
Rob