I'm not sure that it is ever a good idea to open yourself to unknown influences unless you have barriers and strength to handle outside influences. Even the good seeming influences can turn out wrong. To me, it isn't really the ouija board that is at fault. They are just cheaply made toys mostly for kids. It is the KIDS of all ages that are the problem. Young kids are especially easily influenced by rather nebulous leadership.
I think of two little girls that tried to kill a "friend" in hopes of winning favor with the Slender Man. With kids, it doesn't take much and with an ouija board if one of the group wishes they can force some rather extreme things. I have known a few VERY dark kids. Some seem to be just born that way.
I will confess that to a limited extent I was a sort of dark kid. I was often seen as a bit strange and was kind of a loner. Periodic clairvoyance isn't always pleasant and if you tell that something bad is going to happen, when it does, you are kind of blamed. As you get older you learn to not tell as much and become both less sensitive and better at telling the difference between a clairvoyant vision and imagination.