Yes the change in feedback has been frustrating at times. But having been on eBay for 21 years I've had the experience of sellers leaving me negative feedback when I had to file a claim. The one I clearly remember was when I purchased an 8Mb MP3 Player that was really only 1 Mb. Ultimately eBay removed their feedback comments.
Sellers can be upset when buyers don't pay or scam you. Since that isn't going to change all you can do is employ the tools we do have. File the unpaid claims for non paying buyers. Yet many sellers don't follow through and just cancel instead. By far auctions are the worst for non payers. So the only way to guarantee payment is to require immediate payment on all your listings with no best offers.
Bad buyers can leave you negative feedback to which you can respond but be careful how you word as it could make you look bad to other buyers. Since feedback is voluntary I wait until after my package is delivered. This is when I consider the transaction completed.
Some years ago I was selling a Louis Vuitton Handbag at a Fixed Price with the Best Offer option. I accepted a Best Offer four times that wasn't paid. Finally, I received an offer that was paid, but that buyer was a total pain complaining immediately afterwards about the item price, shipping price, taking to long for delivery. Telling me that she was going to return my handbag and that she had purchased another at a better price. I just kept quiet other than providing her a tracking update, and I shipped with Signature Confirmation on delivery. Yet this buyer still tried to scam me claiming she didn't sign for it. It was a different name. While the handbag was in transit I looked up her address on google earth and her Facebook profile because I had such a bad feeling about her. I read that she had recently married and the delivery confirmation showed that it was her husband who signed for the handbag. She demanded I refund her and opened an INR claim which was promptly closed. Still she harassed me so I told her to check with her postmaster, file a police report, and I did file an insurance claim. However, I insured through a third party carrier and the claims agent actually told me the claim was false. Of course the claim was denied. Not only is that buyer is still on eBay, but she resold my handbag. If anyone deserved negative feedback it was her.
Even best offers can be managed by temporarily lowering the price so they can proceed with their immediate payment. If they don't pay raise the price back up. Of course if they don't hurry someone could buy it too. However, I do pay attention to the feedback buyers leave for their sellers. Whenever someone contacts me I read their feedback . That has been helpful in weeding out some bad buyers and blocking them before any transaction takes place.
