I still stick to prepaid satchels with signature, but due to the cost, it appears many sellers are not using these, are any of you encountering more problems?

I use eBay satchels without signature. As they are a subset of C&S, the address is verified.

 

Plus they are significantly cheaper than prepaid satchels (unless you tie up your cash buying in large volumes), especially without paying for a signature. Which can be any adult at the address, not necessarily the addressee.