Hi Billset and welcome to the forums and thanks for reaching out on this! You might want to consider the organic latex mattress by Sleep EZ - https://sleepez.com/product/organic-latex-mattress/
The organic and natural mattresses (the Select Sleep mattresses) are our flagship products. They’re fully customizable, meaning you can order the mattress to be as soft or as firm as you’d like. They’re also fully adjustable, meaning you can change the softness, firmness, back support, pressure relief, etc. AFTER you get the mattress in your home. To be more specific, the 10” is our most popular, and these mattresses normally go out with three 3" layers of different firmnesses - normally the softest layer (or the cushion & contour layer) is on top and the supportive layers are on the bottom. This helps ensure our customers get the right balance of contour for their hips and shoulders but also support for their lower back. If you start with a certain setup and find that it’s too soft, you can unzip the cover and rearrange the layers to get a firmer feel out of the mattress, or you can exchange a layer to make it softer. Additionally, latex mattresses typically last 20 years. If, in 5 or 10 or 15 years you decide you want a softer or firmer mattress you would only have to buy a new layer instead of an entirely new mattress. Lastly, if the mattress starts to break down in 15 – 20 years, it’s normally the top layer that breaks down first, and at that point you can likely just buy a new top layer of latex instead of a whole new mattress and get an additional 8-10 years out of the mattress.
Furthermore, queen, king, and cal king mattresses are available with what we call “split layers,” which means you can have us cut the layers down the middle (from head to foot) so that you can have a different feel / firmness on your side versus your partner’s side, and you can adjust each side independently over the 20 year lifetime of the mattress. About 95% of our mattresses go out with all split layers from top to bottom, and we get zero complaints on being able to feel the split and we get zero complaints about the layers shifting or anything like that, even if you sleep right on the middle of the mattress.
Based on the information you’ve provided, I would absolutely recommend the 10" organic mattress with medium Talalay over medium Dunlop over firm Dunlop for her side and soft Talalay over medium Dunlop over firm Dunlop for your side. The top Talalay layer should provide all the contour and pressure relief needed to avoid any pressure point issues and will add secondary support to the mattress. Secondary support is needed to fill in the gaps between your body and the mattress – back sleepers normally need secondary support to fill in the gaps between the small of their back and the mattress; side sleepers normally need secondary support to fill in the gaps between their mid-section and the mattress, and stomach sleepers normally need this under their belly or in their upper shoulder / clavicle area. If these parts of a person’s body aren’t supported by the mattress, their muscles will work throughout the night to hold these parts of the body up, and by the time they wake up they’ve got back pain. So the top 3” of Talalay latex will provide contour, pressure relief, and secondary support. The remaining Dunlop layers should provide all the support needed to maintain proper spinal alignment and avoid back pain. Please keep in mind that our initial recommendations have a 90% success rate (we only have a 10% layer exchange rate and a 3%-4% return rate) so there’s a 90% chance that the above recommendation works perfectly for you.
Although it’s not likely that you’ll need to rearrange layers or exchange layers, you certainly have the option to adjust the mattress according to you and your partner’s specific needs and preferences, both in the short-term and long-term. We have a 90 day exchange and return period, so you can exchange a layer within the first 90 days for a flat-rate $30 fee for the first exchange and the full cost of shipping for any subsequent exchanges. We will ship your layers first, and we will ship them with extra plastic that you can use to package your current layers, and we will ship it with a pre-paid Fed Ex return label. Also, if you will please call us when you are ready to ship your layers back we will schedule a free Fed Ex pick up for you. You will have 30 days after its arrival to return a layer of your choosing, so you’ll have plenty of time to try a few different combinations with the layers you have and the layer we will be sending you so that you can get your comfort and support levels just right.