It isn't about respect. The upcoming election may be disputed in court and the Administration wants to have as many judges on its side as possible. Even if there is no election related court challenge, there are many investigations of the current administration ongoing and it would be helpful to have more conservative justices for insurance.

The upcoming election will only be disputed by one side, because the other side will have such a clear majority that a dispute is practically impossible.

Both sides have lists for judges not just for the supreme court but all federal courts. Its easier to keep a up to date list then to try to figure out a list when there is a vacancy. They will also often reveal the list or parts of it to get other people's opinions.

I suppose, but the number of days before they bring a nominee to the floor seems a more direct measure.