Hey SD007,
Welcome to TMU.
The short answer is that latex comes in different feels. Latex in general offers a bouncy, floating, and soft feel, that offers a bit of “push back.” Memory foam, on the other hand, offers nice pressure relief (maybe a bit more than latex), but you tend to sink into memory foam. It is more of the sleeping in the foam rather than on top of it. Traditional memory foam is heat responsive, so if you leave your house at 62degrees, the topper will feel firm when you get in, but as your body heats up, and the topper starts to swallow you a bit like slow quick sand, you become surrounded by the topper a bit, and it can get warm to sleep on.
All foams will retain some heat, but latex, particularly talalay processed latex, is more “airy” and is much less heat retentive. Natural fibers such as wool or cotton, down or feathers, make nice toppers, but are not bouncy or floaty, they are soft and cushy, but do compress when you sleep on them and can become firm but soft at the same time. There are a few toppers out there that are made with wool and microcoils and microcoils and other combinations.
This is a good cross section of some options and what they look like.
Various topper styles
Most of our Trusted Members offer natural latex toppers. There are a couple that offer wool toppers and cotton toppers. The fact that you are a lighter BMI, and want a softer more responsive feel, just means you may need a topper with a lower ILD, perhaps 10-16 range or so. If you like bouncy, memory foam is not the way to go. Latex, latex alternatives, will give you the softness and bounce you are looking for. Materials such as the titanflex come in several firmness levels from soft to firm and has a bit of bounce and are more economical as they are synthetic. Natural latex, particularly Talalay processed will be a bit higher in cost, but will last quite a long time.
Horsehair is another option, but it gets very pricey and is not as readily available as all the other options. Only a few folks have them in the USA. I love horsehair as a fill, and have horsehair pillows and they are wonderful to sleep on.