Does an additional latex firm layer balance an additional plush layer

I have a post about “fixing” my DIY mattress stack in the regular forum, and Basilio kindly suggested you might be a good one to ask.

Trying to tweak my four 3" layers of Dunlop for slightly more cushion without sinking too deep: running out of options in moving things around to know if I can keep this mattress. I’m 5 foot 3 1/2, 155 pounds which is a 27.4 BMI. Side and back sleeper.

  • 2 layers of Soft (Soft, Med Soft) over 2 layers of firm (Firm, X Firm) was too soft; caused back pain.
  • 1 layer of Soft over 2 or 3 firm layers is not enough cushion, gave hip pain. I tried it directly on the Med Firm and directly on Firm. I never removed the X firm in any configuration.
  • latest I tried is 2 inches of gel foam topper directly on top of the Soft outside of the wool zip cover so it would conform more, w/Med Firm, Firm, X Firm inside the cover (so only 3 layers inside a cover meant for 4). This seems better, not perfect, one night so far.
  • Manufacturer suggests I use all 5 layers as shown, and add back the Med Soft over Med Firm, so 2 layers of soft again but now over 3 layers of firm vs only two.

Q: Can adding 3 inches of Med Soft actually be balanced out by an extra 3" Medium Firm layer beneath it, so I won’t sink in like I did with 2 soft over 2 firm?

Thanks for any insight you can provide, your time is appreciated.