Hi Erica,
There is a local factory direct manufacturer near you which would be well worth a visit.
http://www.maplewoodcustombedding.com/AboutUs.htm
Other than this, local outlets that will show you the layer by layer construction of each mattress or where you can test a mattress that this information is available online are the best places to do your “lie on bed” testing.
In terms of information that can be very helpful … I would start with this The basic functions of a mattress - Overview - The Mattress Underground and then the other “overviews”. More specific details are in the separate pages in each section if you want more specific or more technical details. Once you have read this you will know more than most of the mattress salespeople out there. Many of the more recent threads also have a lot of information about the different materials and layerings that are suitable for different weights, weight distributions, and just as important … different sleeping positions.
A good set of guidelines as far as things to watch out for is in reply #6 here https://forum.mattressunderground.com/t/latex-mattress
You appear to be fairly slim and your husband is much heavier so depending on the weight distribution and “shape” of each of you and your different sleeping positions … it may be worth considering different layering combinations on each side of your mattress (all within the same height) so that each of you can customize your own side if necessary.
I am 6’5" and 195 and my other half is 5.7 and “about” 130 or so (as he takes a deep breath and prepares for the worst for revealing this :)) but we have similar weight distribution and sleeping positions (primarily side sleepers) so we didn’t need to customize each side in spite of our difference in weight and height).
Hope this helps and feel free to ask if you come across anything that needs clarification or you have more questions.
Phoenix