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... stable, performance, memory use, transparent file formats, documented (API)
- Improve Drag & Drop API 
- Improve TreeView API
- Improve TableView API
- add/remove columns is a mess (see ITableView / TableView)
- Improve provider logic (finding the best fitting view, properties, ContextMenu, NodePresenter etc. for a type)
- Improve IView / IViewContext API, view creation / resolving logic (double-click on item opens view for parent>parent>parent object but can also open view for this object), currently it is too implicit (CreateView changes view.Data to a different object and Delta Shell should check it)
- Use providers for Importers/Exporters similar to views and nodepresenters (what about property classes?)
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