grafio is a close competitor to Lekh Diagram. Shape recognition and customization of shapes are much better in Lekh Diagram.
What Lekh Diagram lacks (if you compare with grafio) is aesthetically good looking GUI.
Apart from that the grafio recently added toolbox for flowchart shapes which is currently not in Lekh Diagram. But many of those toolbox shapes (like arrow) are easily recognized by Lekh Diagram.
As much as a good looking GUI would be nice, please don't do it at the expense of speed/performance and please don't over do it. There is something to be said for a clean simple, but polished look.
