It would be nice if there was some kind of alignment property on the TextBlock component in a Diagram, so that the text could be properly centered without needing to calculate the positions within the area.

Maybe having some kind of "container" component with this property that you could place TextBlocks inside would work.

You should include a flowchart demo for your diagram tool. It is possible - somewhat - but you are not even including a demo for it, while vendors like syncfusion do! 

The way I found out a flowchart was possible was because of the Kendo UI cookbook and cookbook code files. 
https://www.packtpub.com/web-development/kendo-ui-cookbook

Seriously, I don't know why you are not including a demo for a flowchart in your demo list for the diagram tool; this should be a no-brainer to include, and in theory, you should not even have to build anything new, just use the diagram tool you have already made. 

What we would like to do is to be able to disable the following in the Diagram:

- Draggable objects
- Dynamic connectors
- Ctrl+Z effect

In large Diagrams the connections will route trough the shapes itself what is very confusing. I would like to have an option to avoid this behaviour.

Tooltip for Shapes in Diagram

Rad Diagram - Support copy paste from one diagram to another,

Implement containers for the Kendo UI Diagram much like Telerik's RadDiagram for WPF and Silverlight.  The containers need to be able to support connections within parent containers (essentially need to be able to create an entire child diagram within each container).  These containers must also be able to be moved as a unit when the user drags and drops the containers around on the screen.

HTML5 Diagram Control -  allow title editing on shapes and connectors

It would be nice if the diagram control could have undo/redo event.

It would love to have an export feature for Diagram which will give the possibilty to make an export to Microsoft Visio.

It should be allowed to extend the Diagram plot area to more than 20000px and/or to calculate the max scroll width based on the Diagram content.

Automatic Layout and Data Source in case of non-TreeView data

In the diagram control automatic layout and data source works just for a tree view. For example in a non tree view data we would have several levels with items that can have multiple parents. In this case I have to create the items in the diagram manually...it would be nice to update this behaviour and to be able to use the diagram with automatic data source and layout also in the case of a non TreeView data.

The diagram has its own built in flow layouts (left, down, &c.).  I would like to see an interface provided to allow a custom callback to allow a programmer to create their own layout flow designs.  All positioning calculations would be up to the user implementation, but objects that provide information about the current layout while rendering could be provided as parameters to the callback.

When using the diagram control I have been told there is a bound and unbound mode. In bound mode all events are supposed to funnel through the dataSource. While in unbound mode the events should funnel through the diagram directly. I would like a way to combine this functionality. To prevent unnecessary code and logic I would like to be able to provide a dataItem and the shapeOptions that accompany it. Currently if I provide a dataItem then I am reliant on the shapeDefaults requiring logic in the visual function, the change function, and the editable.shapeTemplate function that I wish to provide. Instead I would like to be able to determine the options for any dataItem and provide them when the item is added to the dataSource.

Thanks

It will be nice to create shapes with rounded borders

Add built-in support for guidelines that will be visible as an infinite grid of lines, with a snap-to capability.

Its good to have minimize and maximize the shapes drawn with kendo diagram as seen in this example
https://gojs.net/latest/samples/IVRtree.html

it will very useful when we are drawing with a huge data. we can clearly see the actual flow as required

When connections are detached from shapes or drawn via API with coords instead of shape ends, they don't move with selection when multiple shapes/connections are selected.  When these "floating" connections are selected in a multiselect scenario, they should move with the rest of the selection.

I save the diagram json to everlive by using the save method and load it into the widget with the load method.  My problem is that connection blocks cannot be edited now.  I don't think CRUD should be required for this ability.  

It would be nice if, in addition to "polyline" and "cascading", if there were other options for the shape of the diagram connectors.  I would like to see a "spline" option that possibly follows a similar path to the "cascading" square shape, but flows with curves.   Maybe even a configuration object, instead of a string that could define the parameters of the shape.

{ 
type: "spline", 
mode: "bezier", // or "natual" or any other spline algorithm //
maxCurves: 3, // max number of inversion points in the spline //
curveRadius: 100 // size in pixels //
// any additional properties for configuring the curve, like bezier length, instead of curve radius &c. //
}