Following on from the suggestion about social medium spots, how about the ability to add custom spots for less frequently used sites, such as Likes.com.
Maybe useful for people who want to add business or personal contact methods, and for secondary accounts etc.
It's not a bad idea, but your reasoning doesn't make it appeal to me. I personally don't care what anyone's likes.com is. Do you have any other examples? It sounds more like a way to show what OG's you have on your profile.
I just used Likes as a random example, but any site that isn't on the contact's sheet already basically. Something like your Reddit account for example.