I am not sure if this has been discussed or not--don't have time to read 110 pages.
I do have the text chat, but some of my friends do not. I would like to see a message that says "Thank you for your help!" The "Thanks" is sort of confusing. After a friend helps in a battle and then leaves (quickly) I have sent the "Thanks" to them and then they pop back. It seems like it is a bit sarcastic at this point. Like I was saying 'Thanks a lot for leaving, why didn't you stay?' type of thing.
Also, could there be a message that says "No Problem" or "Sure". How do you reply when someone, who is on menu chat, says "Thanks" after you have healed them, given them a shield, or just helped? The only way I have seen and found is to choose "OK" and that just does not seem to be a decent reply.