the features that make the 60D a slightly higher-ranked camera. The image quality would be about the same,
I guess this is where I get confused. If it is a higher ranked camera shouldn't picture quality be better?
Not necessarily, there are many other things to consider- features that make the photographer's life easier, features that make it more likely that a sucessful photo can be achieved under conditions that may be difficult, the ability to tweak and adjust the machine or expand the system...
Not that the 60D is one- but if you just need a decent car- a Hyundai will do- don't let someone upsell you to a Cadillac. If you plan on building a hotrod, entering car shows or going on rallys- buy a Chevy, Corvette or Range Rover.