I considered having the dog move slightly right and the frisbee move slightly left, and when they are aligned they don't change position anymore, so when you're perfectly centered, you can go for it.
Alternatively, I would've provided indicators for when you're about to get treats, since it does take some quick reaction to grab those last few.
Ultimately, I felt it offered enough challenge to be fun and still slightly difficult. There is a fail state for the game that's not hard to achieve lol