DIY Mattress close to HD Foam and Nectar

Hello there!
We are building our very first latex mattress and would love some guidance! We had a 1.5" latex topper that I liked a few years back but it was falling apart/shedding badly since I didn’t know to buy a cover for it and so I had to toss it. Other than that we’ve been sleeping on the same set of queen firm springs for 12 years. It’s actually holding up well since we’ve had toppers on and off but we have both been tossing and turning a lot lately and also deciding to upgrade to a king.

As a basis of comparison, we bought a Milliard 4" trifold mattress made out of luxurious medium-firm HD foam for our 2-week car road trip cross country recently and loved it. Layers:

We have also been trying out mattresses in store and fell in love with the plush-firm feel of a 10" Nectar memory foam mattress at a store. Layers:

For obvious reasons, we are opting out of petro foam.

Me (F) - 42, 5’-4", 128lbs - mostly side sleeper, sometimes back, sleeps hot. Current problems: Leg soreness/restlessness from workouts worsened, occasional backache, numb arms from sleeping on side.
Him (M) - 42, 5’-10", 165lbs - combo side and back, sleeps cold. Occasional back pain.
(give and take a few pounds)

We love the feel of the medium-firm HD foam of our Miliard trifold and the firmer density memory foam of the Nectar and want to recreate a similar feel for a split King all-latex under $1400, priorities are pressure points relief (more for me) with medium-firm to firm support and motion isolation. He likes a firmer mattress while I prefer a slightly softer one since I am mostly side-sleeping. We both seem to like a layer of transitioning plushness over a medium firm to firm base. We don’t like the quicksand feel that some memory foam standalone toppers provide. I hope this description helps!

I was thinking perhaps:
2" Soft Talalay #19 for me and him (split) - NOTE: The 1.5" blended latex topper we had over our firm innersprings bed a few years back was good but I remember wishing it was softer/plushier/more conforming. It was cheap so don’t think it was Talalay.
3" Soft Dunlop #19 (me) and Medium Dunlop #28 (him); OR, should it be Medium Talalay #28 for me instead?
3" Firm Dunlop #38 for me and him; OR should it be Medium Dunlop #28 for me instead?
8" Cotton Stretch Knit UNQUILTED cover (we like the conforming feel of latex/foam and don’t want a quilted wool barrier.) I think LMF used to have an 8" cotton stretch knit cover. Is it still available? If not, we will get it elsewhere.

What do you think? What would you recommend? Thanks so much!

Hello. Thank you kindly for reaching out! Based on the information you so kindly provided, I would recommend something very close to your suggested configuration. I recommend a soft Natural Talalay over Medium Dunlop over Firm Dunlop configuration. At 128lbs and 165lbs respectively, a 2" or 3" Soft Talalay will provide you with the contour you will both need, while the medium over firm Dunlop layers below will provide you with gradual support. This is the most common configuration ordered by customers weighing under 185lbs.
Thanks again for your inquiry! Please come back should you have further questions!