Hi mantrasia,
While it’s not possible to “diagnose” mattress comfort issues on a forum with any certainty because they can be very complex and there are too many unique unknowns, variables, and complexities involved that can affect how each person sleeps on a mattress in terms of “comfort”, firmness, and PPP or any “symptoms” they experience … there is more about the most common symptoms that people may experience when they sleep on a mattress and the most likely (although not the only) reasons for them in post #2 here.
There is also more about primary or “deep” support and secondary or “surface” support and their relationship to firmness and pressure relief and the “roles” of different layers in a mattress in post #2 here and in post #4 here that may also be helpful in clarifying the difference between “support” and “pressure relief” and “feel”.
These posts are the “tools” that can help with the analysis, detective work, or trial and error that may be necessary to help you learn your body’s language and “translate” what your body is trying to tell you so you can identify the types of changes that have the best chance of reducing or eliminating any “symptoms” you are experiencing … at least to the degree that any symptoms are from your mattress rather than the result of any other circumstances or pre-existing issues you may have that may not be connected to a mattress.
The most common (although not the only) cause for lower back pain is a mattress that is too soft and this would be especially true if you spend time sleeping on your stomach because a softer mattress can lead to sleeping in a swayback position when you are a stomach sleeper.
While it’s only possible to make an educated guess because the only way to know for certain whether any combination of materials and components will be a good match for you with any certainty will be based on your own personal experience (and nobody has a crystal ball that can know for sure) … based on your comments it would make sense that a firmer comfort layer would be less risky and be worth trying.
Phoenix