- To be open source, or open specification/format.
- Easy eaditable (gui/tui/source), that is, primitives. I don't want to edit a text based diagram with a text editor (emacs artist mode).
- Free design features, so I have some control on the presentation.
- Render to text diagram as a first class feature, so it can be integrated in source code/control. From text rendering it can easily be converted to vectorial/raster.
- CLI to render.
- DSL, better with geometric (position, size) and styling features (color, bold face, ...).