My first surprise was the big world of scents -- and how many mediocre ones there are, and how interesting it is to find ones I like.
I started (somewhat naively) thinking I would get a few nice green/forest/pine scents. That is still my holy grail style, and one not yet fully achieved. I long for a perfect walk-in-the-woods scent!
A style surprise for me were fougeres, especially what I call ferny fougeres. E.g., Trumper's Wild Fern or Penhaligon's English Fern. In some ways that reminds me of smells at my grandmother's house, and at the same time it seems so current and lively.
Two surprises I'm still maturing into are violet leaves and oud. Their piercing notes are difficult, and yet I can begin to see how I might appreciate them.