The mattress is a safe thickness as dictated by the Federal Safety Standards ASTM F-2194 and ASTM F-406, and is intended to protect against the risk of suffocation if an infant is placed on their stomach.
We believe your little one will find it very, very comfortable and will be quite happy in their Lotus.
Once your child is 1 year or older, we do offer for a Plush Quilted Sheet for the Crib that is very soft and has extra padding in it. This 1 year recommendation is based on a recommendation from the American Academy of Pediatrics that you do not add any extra padding to a crib mattress until your child is 1 year plus.
If you're interested in reading more about the AAP's guidelines for sleep safety, check out their article.