Flgirlmom,
I’m glad you found some items to test. The Savvy Rest Vitality is plush natural Talalay latex from Radium, in the ultra plush ILD range of 15-20 or so. The cover is a thinner organic cotton casing. I have a 3" topper similar to this on my mattress with the older 2" Savvy Rest Woolsy topper (Disclaimer: I do offer Savvy Rest at my stores).
Regarding your thinness question, OMI does offer a 1.5" version of their wool topper. You may wish to investigate that.
As far as the Celsion topper, that is just the trade name that Talalay Global puts on their blended latex using a small amount of phase change material (paraffin wax last time I was informed) that can assist a bit with temperature regulation, but with the wool topper above the latex layer, I wouldn’t make this as much of a priority. My topper has this same material and honestly I can not tell the difference, and latex itself is quite breathable. I would focus more on the comfort.
Regarding other options, I know there are a lot of sources for toppers (latex and wool) in this post that is referenced often on this site.
-Jeff Scheuer
Mattress To Go