This might answer your question regarding the slow throttle response as quoted from the repair manual.

"The PCM recognizes how the accelerator pedal is being pressed and switches between a few characteristic curves. Eighty percent of the engines power is achieved for a pedal travel of about 50% for an aggressive driver and about 40% for a conservative driver. There is no further difference felt above a pedal travel of 90%.

The characteristic curve for a conservative driver is active after a long drive. Then the accelerator pedal must be pressed down unusually hard to obtain a higher acceleration level."

Try the reset I described in my earlier post. I usually perform that operation every time I get into the car. Seems to work well for me! Good Luck.