Yes so the whole point is that if you DON'T want that "Let's Play" name then make the challenges yourself 
changing the game name
I think the problem is that a game has 2 players. So, the default is the the person who issues the challenge gets to choose.
You're right! Solution: games must have three players. That way every other games is a third of the first and the renaming can start on the fourth.
Or at least something more aggressive sounding than "lets play". Should be something like "die weakling, die" or "Just give up now". I don't know, none of those hit it quite right but you know what I mean.
Where's parametric naming of chess games when you need it?
They could place an ad headline there for basic members
OHH! I love that idea. They could sell that space to advertizers! So your challenge might read "This challenge brought to you by Crest Toothpaste!" or "Another Budweiser Bashup, brought to you by Budweiser!". That's hysterical stuff but almost makes too much sense so we should keep our mouths shut or it might happen.
I'm seeing a "GoDaddy.com" gif ad
HA ha ha ha (lol lol lol for those of you who have evolved into the 21st century).
Most of you guys realy make me laugh. This is a good thing in a sometimes painful world. A couple of you lack humor and imagination, but that's to be expected. One of you is a bleedin' ijit who doesn't know the difference between poetry lines and movie quotes (but also not entirely unexpected).
Ultimately, though, I did get my question answered. Once the game starts, the name can't be changed. This is why I do most of my own challenging. Xqsme figured it out, too. I can more easily recognize the opponent; and it has been a bit of a icebreaker for chat.
Meanwhile, let's let the thread continue. It's quite amusing to read the dumb things people say. (Even when it's me!)
"Oh my God. It's full of stars!"
It wasn't in the original movie, but in Clarke's book, "2001 - A Space Odessy," it's the last line that Dave Bowman utters just as he's entering the monolith in orbit around Europa. I believe in the movie's sequel, that line is referenced.
I think the problem is that a game has 2 players. So, the default is the the person who issues the challenge gets to choose.