As much as I am a command-line guy, using the command line for this sort of thing is just not working for me. (I also tried TaskWarrior, which has dependencies, and is also command line.) I don't want to constantly have to reference multiple sets of outputs in order to manipulate tasks. I left "mh" behind long ago.

I think that I've found a contender in Tracks. I dismissed it before because the available demo site was running an old version and didn't have the features I needed.

The dependency manipulation "gesture" is backwards from what I'd expect, but I think I'll get used to it.