I think it would be good if the mentioned API would always include the "All visits" segment a well. Otherwise in all applications you have to hard code this one. It should be probably the first segment returned in the list if possible.
Actually I think it doesn't make sense or at least it gets just more complicated if this way. Wasn't even sure when I created the issue. Makes other things more complicated such as we would have to introduce properties like "editable" etc. Also some other properties would not really make sense for the default segment so I will just close this issue.