Hi ddcfri,
I’m sorry to hear that your Tuft & Needle mattress didn’t work out as well as you hoped for.
Two of the members here were making an “all synthetic latex” mattress at one point. One of them had two 4" convoluted layers and the other one had three 3" layers but neither one are making them any longer.
Some of the lower budget latex or latex hybrid mattresses I’m aware of are listed in posts #3 and #4 here.
Some of the other simplified choice mattresses besides Tuft & Needle and Casper are also listed in post #2 here and the first post in the same topic may be worth reading as well.
While I can certainly help with “how” to choose … It’s not possible to make specific suggestions or recommendations for either a mattress, manufacturers/retailers, or combinations of materials or components because the first “rule” of mattress shopping is to always remember that you are the only one that can feel what you feel on a mattress and there are too many unknowns, variables, and personal preferences involved that are unique to each person to use a formula or for anyone to be able to predict or make a specific suggestion or recommendation about which mattress or combination of materials and components or which type of mattress would be the best “match” for you in terms of “comfort”, firmness, or PPP (Posture and alignment, Pressure relief, and your own Personal preferences) or how a mattress will “feel” to you or compare to another mattress based on specs (either yours or a mattress), sleeping positions, health conditions, or “theory at a distance” that can possibly be more reliable than your own careful testing (hopefully using the testing guidelines in step 4 of the tutorial) or your own personal sleeping experience (see mattress firmness/comfort levels in post #2 here).
While the firmness level would be “somewhat similar” (they are both somewhere in a “medium” range), they use different combinations of materials so they will have a different “feel” but you are the only one that can decide whether trying the Casper (vs the many other options that are available to you) would be worth it to you.
Phoenix