For the first 35 years or so of my driving career, I always owned at least one convertible. With the top down, you can see more, especially looking up. You feel more out in the world and there is also the smell factor. I would argue that the sense of smell is the second most important sense for exploring the countryside.
As I have transitioned to a motorcycle for my explorations, I've kept most of the good things about the convertible. Ok, I don't get the wind in my hair because of the helmet, but you truly feel like you are out in the world with lots of fresh air, a full view, and all the smells.
There are exhaust smells, wet leaf smells, and factory smells. The summer I worked at the GM Proving Grounds, I was driving the Sprite and I could have told you blindfolded where I was when I smelled this one small factory. The smell was a mix of hot linseed oil, WD40, and something electrical getting too hot. I never did figure out what they made at that factory.
I admit, there are smells that I might rather do without, but the clean, fresh breeze when you come over a mountain pass makes up for any nasty smells.
The most common smell is that of freshly cut grass. Since I have hay fever, I hold my breathe, but I still know its there.
Surprisingly, at least to me, is that the second most common smell is laundry soap. Both strong and easily recognizable, I never realized how much scent I was putting out when I did my laundry.
Its a shame we are more and more isolated from the outdoor world.