I bought my Protege 5 in January 2004 for $13,900 due to it's being replaced by the Mazda 3. I'm on my 7th year and it has been a great car! I have 160,000 miles and I've had few issues. At 120,000 miles it started running rough and I found that the hose connecting the airbox to the intake was cracked. It cost about $90. At 100,000 miles I replaced the timing belt, belts, hoses, water pump for about $1000 through the dealer. Other than that it has been basic maintenance and has been very reliable. It now needs new struts, but otherwise works fine. I hope to get a few more years out of it.
More power and refinement in the engine
Better accessability to the hatchback area (the seats don't fold all the way down like the Toyota Matrix)
Taller 5th gear would make the engine RPM's lower, quieter and probably improve fuel efficiencyter and probably improve fuel economy