I don't think yEd Live would work for me, as I doubt that it could withstand what I'm needing it for. Also it seems to be simpler in a lot of ways compared to yEd, for example the node properties look a lot more sparse.
As for what I'm using it for, Writing, specifically to construct Skill and Perk trees for my literary RPG system. Though it kind of evolved into a 'murder board' with a lot of random nodes containing ideas, plotpoints, lore tidbits, character details, etc.
Also while there is nothing native in yEd, might it be possible to edit/add nodes by delving into the files? And if yes, might there be some instructions as to how to go about it?