The reason I don't leave feedback anymore is because it's pointless. I had an incident with a seller and I left neutral feedback because I was not happy with the service I was provided. The seller called eBay and whined and eBay took the feedback down. You should check and see if the negative feedback you left is still there. If the seller knows what they're doing it's probably gone.
And shipping costs are only going to get worse. I saw a thing on TV this morning that said two years ago you could ship a container from China for a little over $1,500. That same container today cost more than $16,000 to ship. That's ridiculous.