Improve Zone Editer user experience

As a web-hosting provider I would like the DNS zone editor to be improved so that it's easier to use for cPanel end users.

Here are some of the issues we have encountered :

• When you create an MX record, the TTL field isn't editable. You currently have to save the MX record then edit it again to change the TTL.
• When you edit a CNAME record you cannot change the record type. You have to first delete it then recreate it which can cause confusion for end users and maybe even some downtime between deleting the record and creating the new one.
• Lots of third party websites including microsoft office say to use "@" instead of saying the domain, @ should be either accepted and converted to the domain name.
• Lors of third party services require TXT record creation so a +TXT RECORD button on before clicking on Manage would make things easer for en users too