
Growing up a farm boy in Tasmania, surrounding farms would grow pyrethrum as an insecticide. It has both repellent and insecticidal properties and decomposes under prolonged UV, making it attractive from a sustainability perspective. I don't know the odor of pure pyrethrum, but the raw flowers smelled fine.
Natural repellents we favored were tea-tree oil or the classic citronella oils. These would be sold in pump-spray units with the oil dissolved in a volatile organic solvent (e.g. alcohols). The odor wasn't masked with other fragrances.

From Sam 5/8: "Which is more important. The good feeling from using s natural, or the product's perfomance?"
From my experience (people I know), for 90% of the population performance is the key, with natural supplying a warm, fuzzy feeling. The remainder are hard-core naturals folks who will compromise on performance. We've all tried natural products, and most of us have been scared off by a combination of lower performance and higher price.
I think the key is to maintain parity performance satisfaction before "natural" has even been introduced. Performance can be different, but the satisfaction needs to be the same. "Natural" will then put the product over the top to make a winner.