People are so in love with their cars and with this car I'm no exception. I bought a base "s" -- no options at all -- and it is still a lot of car! Power locks, windows, tilt and telescope wheel, keyless entry, GREAT stereo, etc. And the engine is fantastic. You really need to be in above 4k RPMs before it really kicks in, but that is pretty normal for all them 2ish liter 4 cylinders that get max power aroun 6-7k RPM. And when it kicks in it really kicks. Keeping it in third around town and in fourth on the highway keeps the RPMs at a very responsive level. etc. etc. Also it's quite roomy by small car standards, but I would't take a long trip with large men in the back!
Stero. Engine. Styling.
Any improvements already exist as options, so I can't think of anything else. Leather? Already an option. Satellite radio? Already an option. etc.