The Eticket is an issue I guess DL does not want to deal with the issuance. Yes, the transition was a pain but now it seems to run. I bet you it will be like that for all Zedtravel because it will be less costly.
The advantage of having an Ezedticket is whatever you will be in the world, as long as you can call your nonrev desk and have a credit card and email you will be able to get your ticket.
You will not have to go to your airline ticket counter.
B the way if I am not mistaking AF have their Zed tickets electronics.