For me the only thing that needs to be fixed is that when my mouse ever so briefly glances over a contact in the Hangouts pane as the cursor traverses to the ot

For me the only thing that needs to be fixed is that when my mouse ever so briefly glances over a contact in the Hangouts pane as the cursor traverses to the other monitor, that contact's card pops up and stays up indefinitely, looking at me. If it could never do that I'd be happy. Otherwise the gmail interface doesn't really need any improvement. It's email. there's not much special about it.