Recapping my comments on this one:
- you can encourage more social interaction between players either by walling in the dog park or by making the dogs always try to run back there after they escape
- the players falling over is funny but is probably not helping the overall vibe or comedy of the game itself, so I would lock their X and Z rotation
- if you tune this right, it should always be easy to walk in the direction of my dog, and never be easy to walk away from the dog
- the best moment is when you throw an object and chaos ensues as the dog runs off somewhere and other people's dogs also join in. Try to bring this moment out as much as possible
- the movement forces on the player and dog are way too weak right now - makes it hard to get going and hard to stop and generally hard to control. You should have much higher forces with much higher damping, for fast acceleration and deceleration.