I'm a person who buys a lot of cars to try them out and compare. I've found that the Fusion hits a sweet spot for me with a combination of performance, handling, and economy that's hard to beat. I like to drive hard and the Fusion is very responsive. The inline four winds out nicely, the understeer is predicable, and the brakes are good. Its truly a hoot to push on a country road. Fuel economy in evenly mixed city and highway driving is 23 mpg when pushed and 25 at normal acceleration. The comfort level is high; it's essentially a Mazda6 in American clothes. Only the Accord is better and its slightly higher refinement is not worth the higher price to me.
Steering, handling, engine, and brakes. The 5-speed manual is good, but not as good. he back seat is roomy for an intermediate. Standard sound system is better than average. Conti Contact Sport tires are very good.
Offer a model with a set of shocks and springs that tie it down tighter. Offer a good six-speed gearbox, or at least a better five-speed. I would shrink the whole package five percent in size. Weakest feature is large turning radius.