this car is amazing. i bought it with about 100K miles on it, and have put 60K miles in just 2 years or so. The MPG is insane; even though its rated at 39 MPG, i routinely obtain 42-45 MPG. The car is so reliable its amazing. I put 80 mi per day on it, and it hasn't broken down once. Just basic repairs like brakes. I would recommend this car to anyone. Only downside is it doesn't have a lot of pep/pick-up, especially on hills--but hey if you want 45 MPG from a car built 15 years ago, you have to accept the downside.
I'd say stronger engine but then I'd lose the MPG so I'll say it can't be improved upon.