This is a useful extension, I haven’t found any bugs with it! 
I’d say you could add different constraint ‘modes’ that happen when the sprites hit opposite sides. For example:
- The default current mode, where the camera stops to force them to walk together
- A ‘slow’ mode, where one sprite pushing on the right side of the screen could slowly drag the camera and the other sprite to the right
- A ‘fast’ mode, where whichever sprite is hitting the wall takes control of the camera and pulls the other sprite along at full speed
These are just camera centering methods I’ve seen in other engines that could be useful : )