Yed is swell! I have two feature requests:
• Navigation Mode—where you can move the diagram view in directions away from mouse movements— is useful, but somewhat unorthodox.
Will you consider adding a standard Drag tool (icon: open hand) so we can move the diagram by clicking and dragging anywhere on it? This tool is found in virtually all other graphics programs; most users would find it quite intuitive.
I can't speak for everyone, but personally, I'd much prefer to be able to move the view at any speed, rather than being limited to Navigation Mode's single speed. It also requires an extra mental step to process the opposite movement from what you actually want. (People think in different ways; some users, such as physically disabled people, may find this particularly challenging.) I also find NM's movement speed somewhat slow, and think that being able to move the view more freely and naturally—like you'd move a paper diagram on a desk—would make Yed easier and more fun to use.
• Double-clicking an object currently has no effect. (It's just selected, as though you'd single-clicked it.) This seems like wasted functionality.
How about letting us double-click an object to create or edit its label? It's simpler and faster than the current menthods (selecting the object, then pressing F2; or right-clicking it, then clicking one of the Label context-menu commands). Of course those methods would still be available to people who preferred them.