Mobile phone number in profile, pull nicknames from contacts, nicknames across servers

I'm a new Discord user and am trying it out as a WhatsApp replacement. The first thing that I noticed is that I'd like usernames to follow my contacts on my mobile.

What I'd like as a feature is for people to optionally add a phone number to their profile, and for Discord to read my contact list. Discord would then optionally identify my contacts that are also using Discord and propose to contact them in the app, and would use the contact name as their nickname across all servers.

If not that, I'd like to be able to manually assign a nickname to people that will persist across all servers (this would be specific to me; like an "alias").