Given that the main Eating Disorders forum has had only 3 new threads in the past 3 months, you're more than welcomed to start threads in that existing forum on the topics you proposed. While not an eating disorder per se, picky eating can lead to other mental health and relationship issues in a person's life and is therefore appropriate to that forum.
We generally don't start new forums any more. We encourage members to use the many under-utilized existing forums whenever possible.