Since ebay instituted their new ratings system, I've never seen so much begging from sellers. Seems like half the things I get have some pamphlet in there about how anything less than 5 stars will kill a puppy or something.
I don't beg for anything. I enclose no notes or anything like that with purchases. I give excellent customer service and quick communication. I *earn* my high ratings.
I just leave people to their own devices, buyers or sellers. I typically ignore begging letters. Had a few of them but I usually do my feedback in batches so it can take some time for me to get around to them.