I should have worded it better in the documentation, and I'm going to update the description of SceneObjectGroup now. Let me clarify:
A SceneObjectGroup IS an array. So you can do:
// and all the things you can do with an array
All the wade functions such as wade.removeObjectFromArray(...) will also work with SceneObjectGroups.
However it's an array that has got some extra functions, so you can also do
// and some more functions as documented
In addition, you can also call all of the SceneObject functions on a group. These will be executed for each object in the group.
// and all the things you can do with a SceneObject
Other than resizing the group, what other functions for 2D transformations do you think are missing?
Regarding TextSprites and tweens: yes that is a good point. In reality it only applies to the size of the TextSprite, you can tween everything else (opacity, position, etc). So in practice, the only thing you cannot do is set a TextSprite on a path that changes its size while the text also changes. That is going to be a bit tricky, but I'll try to think if there is something we can do to make that possible.