I have no problem with people deleting art by me. It can be for any reason from the character got a redesign to doesn't fit the personality to just straight up not liking it. No hard feelings at all! I've definitely bought characters in resales where the art didn't match up with what I wanted to do so I shipped it off somewhere else. If I paid for the commissioned art along with the character then it seems fine since most TOS don't even cover that. It was a paid for service ya got the right to use or not use. Its kinda like buying a character. You can choose to not use it or even wipe it from existence from your account. Those that do have it in their TOS and get very, very upset over it I try to avoid as much as possible to avoid conflict.
Not posting all the art you receive is fine too! Some people only wanna showcase the best pieces that show how they want characters seen. Some only want refs up. Others just don't wanna upload. It's all personal choice.