Ah! I get it now. You want People Hub to be separate thing and you want Phonebook to be a separate thing, right?
So when you press "Phone" - you see phone book, dialer and recent history.
Then a separate tile of "People" - you see only all people and what's new feed.
Then a separate ME tile - you see only what you've been up to and your notifications.
It might not be "integration" that WP is built around. The way I see it is keeping in mind what they said during 2010 launch. "You don't have to leave, open an app or exit an app to do something different". Contact cards for example, once they are linked, they have all the ways you can ever contact that person. In case you change your mind once you are in phonebook and you think, "Ah, I might just tweet him, he checks it more often", then you have that facility in current situation.
In your scenario, you would exit phonebook. Go to people's hub, find him again and then tweet. Same scenario, now you are in People's hub and think, "You know what, this is SO unprofessional. I should just rather drop him an email". In this case, you have to exit your People's hub, go to email app or phonebook, find him, email him. But in current set up, all you do is, hit back button, tap on email and voila!
I do understand the frustration of seeing those useless peeps you don't want to see, but such are our social lives!
I see this as a feature that really helps me. Those scenarios I discussed above, have actually happened in my real life and I found it so convenient to be able to just tap around and do stuff without opening an email app or separate social networking app.
I only see a single disadvantage for someone like me who saves people with weirdest nick names in phonebook. So my phone NEVER automatically links my contacts with their facebook etc like everyone else always talks about.