Hi J-Dude,
There is more about mattresses and sex (particularly in relation to less resilient materials like memory foam) in post #2 here.
Some of the better latex and/or latex hybrid options I’m aware of that are in lower budget ranges are listed in posts #3 and #4 here. I don’t consider the Casper to be a “latex” or a latex hybrid mattress because there is too little latex in the mattress to put it in that category and with the memory foam under the latex it would also have less of the more resilient “feel” of latex as well (although there are some people who may prefer a combination of latex and memory foam because the choice of materials is always a personal preference).
I would add a “ditto” to tamaracks comments here as well.
There may also be some local options that are well worth considering as well (or that may be good choices for testing different materials or types of mattresses) and if you let me know your city or zip code I’d be happy to let you know about any of the better options or possibilities I’m aware of in your area as well.
Phoenix