Here's something that Steam should implement that's simply better on consoles.
Allow a second player to log in with his own account to get achievements and get his name displayed properly instead of "GAFHaunted(1) or Guest1".
Example: I can locally play Rocket League with my friend on his PS4 and we're both using our respective PSN accounts because I can log in with my account on his PS4 (without signing him out). If I locally play Rocket League with my friend on PC, only one of us can be logged in with the proper account, the other is a nameless guest.
I heartily agree. I have a similar Rocket League PC story. Had Valve ever said whether or not that is something they would allow?