Thor Brag..kind of. :)

Thor's been working on a sit-stay and he has almost got it!
I make him sit-stay before he eats, and before he can go outside to play.
I taught him to do it before going outside by making him sit-stay and then opening the door, and if he got ansty and tried to go out, I would just close the door and start over.
He is 100% when I make him do it to go outside.
He's 100% when I make him wait for food. (I have also taught him a wait command for giving treats and taking toys)
But he's only about 80% when I have him around distractions. But we're working on that.
 
Anyone want to suggest some new behaviors I can clicker train? I can't think of anything right now, but I want to expand his learning to other things. Thanks!