Can I view all Project types in the Projects Pipeline at the same time?
Simply, the answer is no, the reason being that different Project Types have different stages. You can however use the filter to view all Projects of a chosen type.
How to change the type of Projects you view in the Projects Pipeline
All Projects conform to a pre-defined type which you can name. If the Project Type selected in pipeline view is not the one you want then simply change it to the correct Project type by selecting it from the Project Type option: