Hi jege41,
The smell of the different types of latex depends on the compounding formula that is used by each manufacturer and as you noted it ranges from a sweetish smell to a more rubbery smell. The actual compounding formula that each manufacturer uses is a complex and closely guarded secret and not disclosed. The most reliable way to know that any latex smell isn’t connected to any harmful VOC’s or harmful compounds in the latex is to make sure that it is certified by a reputable testing agency such as Oeko-Tex or Eco Institut.
The Talalay you are likely to encounter would either be made by Latex international or by Radium … both of which are Oeko-Tex Standard 100 class 1 (safe for babies) certified.
The “feeling” you are describing sounds like some kind of shear pressure (horizontal “stretching” pressure vs vertical “compression” pressure) and could come from sleeping directly on the highly resilient latex (or perhaps with only a very thin cover on it). A mattress pad with natural fibers or materials or even synthetic fibers, a thicker mattress protector, a good topper cover, or even a thin topper using less resilient material would reduce the surface resilience and tension and change the surface feel of your sleeping system with little alignment risk and likely solve the problem (assuming this is what it is). Post #10 here has more information about mattress pads may be helpful.
I would probably hesitate to add anything that was 2" thick if your mattress / topper combination is already providing you with good PPP and focus on changing the hand feel rather than the pressure relieving properties of the system but if you have some “room” for some additional thickness and softness on top … then the Seven Comforts would probably be a little less risky for alignment than the equivalent solid layer of latex because the latex inside is shredded and will displace a bit under more “pointy” pressure points rather than just compress.
Phoenix