Every snowflake is unique. Every fingerprint is unique. These facts may be interesting, but they don’t mean that every snowflake or every fingerprint is interesting.
Yesterday I was editing some copy and came across a description of the brain as “this unique organ”. This was meant to be a compliment to the brain, but instead it’s a hopelessly empty description: all it says is that we only have one of them.
Another unique organ is the gallbladder. So is the spleen. And the appendix. But so what? A lot of things are unique in some little way, and if you look in close enough detail, technically everything is. The brain, though, is unique among organs like a phoenix among sparrows, not like a snowflake among other snowflakes.
If you want to make something sound interesting, then think about the qualities that make it unique (or at least distinctive).
What sets the brain apart from the other organs? It’s complex, it’s mysterious, it underlies our mind rather than merely physical functions (although its involvement in processes all over the body is also remarkable). It has these qualities uniquely.
So focus on the qualities rather than the bare fact of uniqueness in some undisclosed respect. The brain is uniquely complex, it’s uniquely mysterious, it uniquely underlies the mind. These statements all carry weight.
Or, if you prefer not to go into specifics like that, you could use a word such as ‘unparalleled’, ‘matchless’, ‘exceptional’ or ‘outstanding’. Only the first two truly imply uniqueness, but all of them – unlike ‘unique’ itself – put the thing so described on a pedestal and tell us that it’s well worth a look.