Thanks for mentioning TALA. I feel like TALA does add more control than Mermaid, but in spirit sits closer to Mermaid than Reladraw. It keeps the auto layout, but with extra ways to coax the diagram into a different shape, by saying things like "keep this node pinned over here" or "keep these nodes close to one another".

For the diagrams I usually want to create, that's still not enough control to create what I envision.