The Miata is one of those cars people just awe over, you can't help but name it, you want to call 'her' something. The sleek curves give off a sense of class, while the small, but cocky stance says "I want to play". The Miata, in my opinion, is underrated, it has enough power for most people, and enough aftermarket support for the rest of us. A light-weight rear-wheel drive car is just one of those things that any generation could admire. Cruising the interstate with the top down, wind blowing.. You can't resist but feel that you're free.
I would have to say that my favorite feature is the gas pedal... Just kidding, in all reality, my favorite features would be the easily accessible sound system, easy to change out and upgrade if you needed, and the other would be the abundance of space in the engine bay.
With the Miata you'll definately want to upgrade to a short-ram intake system, and probably an aftermarket exhaust. And you'll definately not want to skimp on the sound system, a good high-quality amp and component speakers with a good quality head-unit will do wonders for this car.