It looks like they borrowed too much from the iOS Contacts app. It really could use to have more control over the presentation (different backgrounds, formatting of the contact display). Feedback to Apple might be in order.
Yes, I have once again reported the problem that is easy to demonstrate with Contacts (noticed someone else out there had noticed a problem with dragging contact cards to groups). Things works as they should nearly always the first time Contacts is launched, but never the second if a card is opened from a mail in the Mail app the second time the card itself is opened instead of taking you to the card in Contacts as one would expect and what happen the first time (this always happens and has done so for maybe 4 years now … but serious usability bugs usually takes about 6 years fix for Apple … or sometimes at least …). If you search for a contact and then try and drag the contact to a group in Contacts – good luck! – It can work once or more, but it will eventually stop working until you restart the app.