I have always had rules about activities.

I have five kids and have been in many different phases at different times.

The little ones NEED to be home.  
This isn't a want, it is a NEED.  
In fact the children that fight it probably need it more than others!

Balancing activities can be hard for families. I taught a class at a Waldorf school several years back on spiritual parenting and bringing the center back to our lives. One of the participants was a dad that had a child in the school. His complaint was that he was in the car all day, after school there were activities and it was making him crazy - he only had one child! I told him to put his foot down and stop trying to give his son everything. His son really needed DAD. The Dad didn't last long in my class, I wasn't giving him the answer he wanted. Sometimes that happens in life, the answer that is appropriate may not be the one we want to hear.

To maintain a healthy rhythm, keep control of outside activities.