Hi. I love the feel of the Vi Spring Coronet in medium firmness with the standard tick and no divan. However, I wish to order 100% cotton tick instead because I want a natural fiber. I was told that the cotton tick will feel firmer than the standard tick. Will it be substantially firmer enough to warrant dropping down to a soft mattress with cotton tick to achieve a similar feel to the medium firm with standard tick? Or ...would a soft mattress with cotton tick be softer than a medium mattress with standard tick? I.e. Is the difference in feel of the cotton tick slight or substantial enough to warrant adjusting mattress firmness? thank you for your informative site!