Buyer Satisfaction

Anyone else have major issues keeping buyers satisfied?

I have pretty much resolved to just say, "F*ck It"

My Star ratings are suffering and I don't know why... specifically the Item As Described and Shipping Charges.  What I do for the description is include the manufacturer's stock photograph, describe the fabrication, and style to the best of my ability, measure each item personally, include accurate measurements in both inches AND centimeters, and point out any features that may not be noticed from the photograph (if any).

I have EBay and USPS calculate exact shipping and have a very, very low handling charge which doesn't even cover the cost of time and supplies.

I just don't get it.

I reply to any and all questions promptly, I take returns with no questions asked, I put little thank you notes in each package, I send packages out immediately upon payment (I make drop offs to the PO ever single weekday).

Still... I have 4.6 - 4.7 ratings for charges and description and 4.8 - 4.9 for shipping time and communication.  I'm really not sure what else i can do at this point to improve my methods.

What do you do?  How are your ratings?