A timeline view like Flash where each layer has a visible timeline would be of great help in synchronizing individual layer animations with one another.
I don’t know if we think about the same thing, because I do not use Flash, but…
I think that a layer timeline and a movie timeline is somethin like that…
Similar to this?
Having used both systems, I think I can lend some clarity:
A Synfig “layer” is roughly analogous to a Flash “symbol”, In Flash, a “layer” was an arbitrary means of grouping symbols at a particular Z index. The timeline appeared separate, but all the layer timelines were in sync with one another. While it lent itself to organization, it had no actual unique features - you could create identical Flash animations on one layer or 150 layers.
I agree that a movie timeline is somewhat similar, though not the same. I’m not certain that Flash’s definition of a “layer” would fit very well into Synfig’s design. If it were implemented in Synfig, again, it would simply allow for arbitrary organization and grouping of Synfig layers on the timeline.