My driving pattern (Corolla 2.0) seems very similar to yours. In winter, on winter tires (16 inches), I get around 47-50 British mpg, if I push it a bit. That means ok quick accelerations and around 70-81 mph (the Danish speed limits) on the highway. However, since Xmas I have been conduction a little experiment, trying to push the mpg as high as possible. That means keeping at around 53 mph together with the trucks at very constant speeds. That sucks a bit (a lot actually), but for the last 2000 miles my average mpg has been 59 mpg. It's impossible for me to get above that, at least given the circumstances (winter tires, constant rain and wind, 4-8 degr. C). All mpg are measured, not read from the info screen.