I like to share that Shapes class has been deprecated in Aspose.Slides for .NET and has been replaced with ShapeCollection class. However, the Shapes class is still there in Aspose.Slides for Java and has not been deprecated.
You are right as it is planed to replace all the collections classes currently in future versions but we will share the information accordingly. Slides will be replaced by SlideCollection, Shapes with ShapeCollection, Paragraphs with ParagraphCollection. Similar replacement will be conducted for rest of collection classes.