Hi bolecailey,
I’m glad to see you had a chance to test some talalay and Dunlop latex so you can feel the differences between them. With your weight you certainly won’t “need” 4 layers although some people may still prefer them either because of the additional layering combinations that are possible or because they notice a difference in how a thicker mattress “feels”. I know that Shawn is familiar with the Savvy Rest mattresses and they would be close approximations (their Talalay comes from the same company … Radium)
The Dunlop in both versions would be the same (100% natural Dunlop) so if you were choosing Dunlop there would be little point in choosing the Organic line outside of the differences in the cover. The Talalay in the natural line is blended (about 30% natural and 70% synthetic) and in the organic line the Talalay would be 100% natural rubber. There is more about the differences between blended and 100% natural Talalay in post #2 here but in terms of “safety” they both are tested for harmful substances and VOC’s to the same testing standard by Oeko-Tex Standard 100 Class 1 so there would be little to no difference between them.
There isn’t a separate bedding section but there is a reference post for sheets in post #7 here and the other posts and topics and sources of information it links to that should be helpful 
Phoenix