This past weekend I finally got around to changing our the pressure sensors to using a Infrared Proximity Sensor Long Range - Sharp GP2Y0A02YK0F I got off Sparkfun a few months ago.
The range of the sensor is up to 60" which is more than enough to detect someone going onto the staircase.
I added some buffering in the code that does the detection to limit any noise that may occur. It also allows me to filter for smaller objects going by quickly from triggering the stairs (my dog).
It is working great and I'm much happier with this setup over using the pressure pads. A person no longer has to be sure to step in the middle to trigger the lights anymore.
I also added a new animation to the staircase.