100% natural isn't necessarily good, because, as you point out, natural materials are fleeting. Luca Turin said it well, synthetics give the skeleton, and naturals the flesh. It is no surprise that all natural perfumes often end up smelling similar, a spicy floral mix that feels a little spineless. Also, there are perfumes that are almost entirely synthetics, and yet smell absolutely natural. An example would be Diorissimo vintage, a lily of the valley that's entirely replicated artificially yet smells wonderfully fresh an natural. Indeed, if I had to choose a perfume that smells natural, I'd say Diorissimo vintage parfum.
As for ingredients, I want to single out JAR. Some of its perfumes contains tons of natural extracts, like the tuberose (Eclair), and, I suspect, Jardenia (Gardenia doesn't really exist as an extract, but I believe that some companies do extract small amounts of it).
I should also mention some ingredients that, no matter how natural, end up smelling synthetic nonetheless: orange flower and, especially, linden. Tauer's linden contains tons of natural linden extract, yet it cannot help giving off a household cleaning vibe.
As for the most horrendously synthetics, Turin's triad is Amarige, Poeme, and Spellbound. Hard to argue with them.