Hi galapagos,
Unfortunately choosing a pillow is like choosing a mattress and there are too many unknowns, variables, and personal preferences involved in choosing a pillow to make specific suggestions or recommendations for someone else. There is no single pillow that is “best” for any particular situation or “symptom” because the goal of a pillow is to keep your head and neck in good alignment in all your sleeping positions and which pillow does this for any particular person or on any particular mattress will vary widely from person to person. In other words … a pillow that works well for one person with upper back, shoulder, or neck issues may not be suitable at all for someone else with similar issues.
Pillows are also a very personal choice and different people will have very different pillow preferences or different opinions about what they perceive as firm and soft or the general type of pillow that “feels” good to them but some of the information in the pillow topic here and the posts it links to can help you choose a pillow that is the best “match” for you and the mattress you are sleeping on.
Phoenix