It partly depends on how much extra foam you’re adding on top of your mattress. If you pile on too many layers above the mattress’s current comfort layer, especially more than about 6ish or more inches of foam above the mattress core, the support layer underneath can’t do its job properly. The softer layers on top start (which are under your 44ILD topper) acting like the support, which they aren’t designed for. That can lead to poor alignment and the kind of soreness you’re feeling.
A 2-inch topper, like the one you liked before, will adjust the feel of the mattress without overpowering it, if you still have that topper, it may be worth a shot to try it. But a 3-inch topper, especially something as firm as 44 ILD Dunlop, can completely take over the feel of the bed and make it much firmer overall. Talalay latex, even when firm, usually feels lighter and more responsive than Dunlop. Firm Talalay usually ranges from about 36 to 40 ILD, while extra firm Dunlop can reach 44ish ILD or more and tends to feel denser and stiffer.
Since you’re waking up sore and feel like your hips and bottom aren’t sinking in enough, the surface is probably just too firm. Adding a 2-inch Talalay topper in a medium to medium-firm ILD (around 28 to 32) could help with pressure relief without making the bed feel too soft. You’ll still feel supported, but with a bit more give in the right places.
That said, stacking a 2-inch Talalay on top of a 3-inch Dunlop on top of the mattress’s own foam adds a lot of extra thickness. You may be better off replacing the Dunlop with the Talalay instead of layering them (but, it does not prevent you from trying it!) That would reduce the total foam on top and let the mattress core actually support your body, while still giving you the contouring you need.
If you want to experiment before buying anything, try folding a down comforter in half and sleeping on it. It’s a simple way to see how your body responds to a softer surface.
Whatever you modify, do it one layer at a time. It is easier to correct and understand what is happening, when you change one component at a time rather than 2 or 3. If you change multiple layers at once and it works, home run. If it doesnt, you really dont know what is causing the problem.
Although someone like @Arizona_Premium might get right to the heart of the mattrer and say just add a 2” medium Talalay and call it a day. And if he says it, I would believe him.
Maverick