Hi reddysr and welcome to The Mattress Underground 
Glad to have you here!
I am not sure what you read since finding the TMU website but you would likely benefit from reading some of the main site articles that have the basics of what you need to know and how to navigate through the shopping process. Only after reading those I’d top it up with some forum readings to add more depth and see what other people with similar body types, needs and preferences have found. I’d start with The Mattress Shopping Tutorial for an overview of the mattress selection process, as well as the Mattress Specifications You Need To Know to compare them to And the Mattress Durability Guidelines to and become more familiar with materials and components used in mattresses.
There is no real best or worst in mattress materials; Many consumers enjoy memory foam and hybrid mattresses over latex, and many others are totally ‘pro-latex’…its’ all a matter of personal preference. What you can and should do is decide which materials just don’t suit you. You don’t say what type of mattress you are currently using, but in your case yes latex is a good choice as is one of the most breathable foams and will sleep ‘cooler’ than a memory foam mattress. You may want to read this post to learn more about microclimates and sleeping hot. There are many options so it’s good if you can ‘cross off’ some mattress types so you can narrow your search.
If possible, the best method is to try out various types of mattresses to see how they feel in person, as you have done with the latex mattresses you have tried.
Thanks for providing your personal stats. When trying or considering any mattress I’d make sure to make a note of the firmness or ILD of each layer and their position within the mattress. All layers work together and each will affect each other. The layer material and firmness are, again, a matter of personal choice but again this info would make it easier to give you some input. Generally, back sleepers want good support to keep their spine in neutral alignment. As you are in a normal weight range you won’t need a thick mattress to get a good balance of support and plush comfort. A firm support layer with medium transition latex layer with a plush comfort layer could be all you need. The only way to know if this combination is the best fit for you is by trying out similar mattresses in the local store.… Talalay is also considered ‘bouncier’ than Dunlop, and feels softer because it allows for a deeper cradle in the same ILD… so there’s also type of latex to decide on.
I will say that many of the Trusted Members of the site carry all-latex and latex hybrid mattresses, both in configured models as well as separate components for DIY builds if you wanted to go that route; They are very experienced in matching consumers to meet their needs and preferences. For instance, Arizona Premium offers several different types and thicknesses of latex mattress, including a 9.5"Ultra Plush Mattress
While DIY Mattress can help you select components to create your own customized mattress, and Custom Sleep technology creates a personalized mattress you can call them for a free consultation or you fill out a body profile and discuss what you are looking for. By providing any of these manufacturers/retailers with a small bit of information about you, (your stats, sleeping style and history) they can guide you through the available choices, and according to their policies they can exchange layers if they do not work for you.
Don’t lose hope! Your research combined with the years of experience of a knowledgeable manufacturer is the best way to get a mattress that suits you and that will last for many years!
~ Basilio