You know, my favourite season tends to be the one we're in for about two months, and then it's the next one. So right now it's fall, especially because this summer has been rather trying, both weather-wise and clothing-wise.
I smell the seasons too. Fall has that crisp, wood-smoke, leaf-mould smell to it; winter has the very clean smell of frozen earth and snow; spring has the rich fragrance of the awakening earth and budding life (so different from just thawed earth that you get in a winter thaw); and summer has that baked or steamed odour of mature vegetation in the sun.
I suppose the transitional seasons are the easiest to dress for, with so many more possibilities, and the quirky weather meaning there's more variety of conditions to dress for too. Summer is all about trying to look good in minimal clothing - quite the challenge when you have less than a model-perfect body. Winter (at least in my climate) means bundling up so much you can get lost in heavy coats and warm boots. But in spring and fall almost all my clothes get a chance to play at some point, layering comes into its own, and the smell of change is in the air. They always feel like the seasons of opportunity to me, in almost every way.
I have sometimes wondered what living in a tropical climate would be like, and I have come to the conclusion that giving up the seasons would be a major sacrifice. I like variety.