Semi-amateur Seller Questions

I've been selling on eBay for about 7 years now. I sell maybe 15-20 things a year. It seems like in the past year, the power has severely shifted toward the buyer. I get many more unpaid items now or returns for no real reason other than the buyer doesn't want the item. I just have a few questions for other sellers.

1. What is an acceptable amount of time to expect payment? I've never bid on anything on eBay that I couldn't pay for within 2-3 days of auction end. But I've got people that wait 10 days to pay, tying up money and my item.

2. Is there anything more you can do to a buyer who doesn't pay other than giving them a no-payment strike and hope that it hurts what they can bid on in the future?

3. When eBay rewrites their policies, do they ever ask opinions of sellers? I feel like I've had one or two surveys in the past sent to me, but I think a lot of buyers would agree, something needs to change to balance the power a little more.

Thanks for any answers/opinions you can give.