Hi Drackean,
Thanks again for your patience and gentle approach. I appreciate it! 
Diagnosing and troubleshooting an old mattress is not always that straight forward …you’d need to know the materials used within your old mattress and look for any potential visible sagging or signs of the foam breaking, virtual impressions, and mattress failing along with how your own body interacts with it… Poor quality materials would lead to the mattress prematurely breaking down. This issue may be further compounded by the use of comfort layers that are too thick and/or too soft.
If your current mattress that has thick layers of lower quality polyfoam in the upper layers such as in a pillowtop …as it starts breaking down it will gradually put you “over the line” and the mattress may no longer be suitable for you (even though it may still work for your wife with a different BMI body type or sleeping positions). I am not sure if your mattress is still under warranty but unless there is an obvious defect, loss of comfort and support from foam softening would not be covered (even though it’s the most common reason people need to replace their mattress). If you wish to do some in-depth mattress diagnosing as part of the learning curve for future mattress selection there is some information about the many different symptoms people can experience on a mattress and most common causes behind them in post #2 here that may be helpful to you.
In general, issues with “pain” earlier in the night tend to be surface comfort related, and issues with “pain” in the morning tend to be more alignment (deep support) related, Lower back pain and Frequent repositioning is one of the signs that your mattress may not be meeting your specific deep support and comfort needs. For someone with lower back issues on a mattress … the first place I would look is the thickness and softness of the comfort layers. What can often happen is that the heavier parts of the body (the lumbar pelvis area) will sink down too deeply relative to the lighter parts of the body which aren’t sinking down as much. The sinking into the mattress is not even for all parts of the body and that spinal alignment is not “neutral”. In this case, the pelvis will tilt which leads to the lumbar curve not maintaining its neutral relaxed position. You probably need to be closer to the firmer support layers that “stop” the heavier lumbar/pelvis from sinking too far. There are some general guidelines as to what tends to cause back pain in post #2 here that you may find interesting
Your pictures show a good posture and spinal alignment when laying on the edge/perimeter of your current mattress, but I am guessing that this is not in your habitual sleeping area and that you’d sleep more towards the center of the mattress where most of the mechanical stress would occur and where the foam(s) would first start breaking down, softening, and losing its supportive properties. The pictures taken of you being placed towards the center of the mattress may be a bit misleading but I do notice more sinking-in than when you are on the edge. Generally, those photos also show good alignment, but if the foam started to break down it would have less resilience and would not fill in the gaps to offer support for the recessed parts of your body.
Again, when you are dealing with alignment issues (often lower back issues) … then it’s usually about some part of your body sinking DOWN into the mattress too far relative to the others. Assuming that your mattress foundation is sturdy, flat, and offers a good central support without sagging, your lower back pains can be the result of either mattress support layers (such as an innerspring) being too soft or comfort layers that are too thick and soft which can allow some parts of the body to “travel” too far. It can also be from comfort layers that are too thin or firm or support layers that are too firm where the “gaps” in your sleeping profile (such as under the lumbar curve or waist) aren’t being filled in and supported which can also allow the more recessed parts of the body to sag or “travel” too far. These can both lead to pain and discomfort in either the back or joints when either the spine or joints are outside of their “neutral” alignment.
While your description is a fairly good assessment of what is seen in the photos about good posture and alignment, I’d try to focus more on how it feels rather than how it looks. See my reply to a recent post with similar questions about spinal alignment that may be useful in trying to understand your current landscape.
Glad to see that in your new mattress hunt you moved away from getting a pillowtop with unknown componentry that may contain lower density polyfoam. They can have a great “showroom feel” but that feel doesn’t last very long …with over 3" of polyfoam is even worse (the lower density polyfoam there is the more effect that foam softening will have). These guidelines will help you avoid most of the worst choices when you are mattress shopping.
Assuming that you chose the right balance of comfort/support for you, the Latex Albizia hybrid mattress does look like a good product. The bed is listed as having perimeter support and the zoned pocket coils are rarely the weak link in a mattress. If you primarily sleep on your back than the 2" Talalay Latex of 19 ILD (most likely from Vita Talalay) maybe not supportive enough and cause again alignment issues. Post #2 here has some generic guidelines for different body types and sleeping positions.
All foam materials will both soften (virtual impressions) and/or develop visible impressions to some degree over time and won’t stay perfectly flat but if they are higher quality and more durable materials such as latex they will be significantly less and take longer to develop than lower quality and less durable materials and any minimal softening or impressions won’t generally affect the comfort and support of the mattress. Latex, in general, is the most durable of all the foam materials and generally holds up very well for a very long period of time.
I hope this helps … it’s nice to see that there are still people who are taking their time rather than rushing to replace a mattress quickly and go through the stress of hurried decisions and more “urgent” research.
Phoenix