Of course, this might just be me, but having a slightly better explanation of in-game chat would be nice, because my 1st online game I couldn't speak at first in chat. Thankfully someone told me that you press ENTER to chat.
I do agree that people would still need to be able to type out messages in game since not everyone has or wants to get a microphone. (I really don't understand why some hardcore gamers don't want to chat in team games. I know a couple guys who play first-person-shooter PUG matches where just about everyone else has microphones but they themselves refuse to purchase or use one.)
The chat commands could be part of the online multiplayer tutorial. Maybe they could make people /w "Game Tutor" Hello in order to continue to the next step. Just so you know, here are the commands:
/ignore "Name" -- ignore someone in chat.
/a -- ally chat
/w "Name" -- whisper to someone
/wf "Name" -- whisper to a friend and also to whisper when a game is lagging.
/r -- whisper back to the last person who whispered to you.
/f -- send a message to everyone on your friends list.