Each phone number you have should have the ability to upload its own voicemail message. We use different phone numbers to track different marketing channels and the only way to do it now is to assign it to a user, but we don't have 30 staff members, nor do we want to create 30 dummy members and 30 dummy emails and assign a member to each number.

Additionally, you need a tab where you can listen to each voicemail, and it shows the number the contact called into (Twilio #) as well as the called from number (also show contact name if already in system)

This really is a critical feature that I'm surprised doesn't exist already.