I'll break the ideas in points:
1)
Timetrack: I find animating in Synfig far more comfortable than the likes of Flash, but there is a minor annoyance that slows production speed down. There's no bugs or whatever, but we do require to "re-arrange" the UI a bit.
For the time being we can only see/edit the waypoints of individual layers, but an animator usually requires quick references to keyframes and their locations (and switching between layers constantly proves to be a distraction). However, Synfig
does have the ability to show grouped waypoints in a single frame when an entire encapsulation is selected, so why not group waypoints of layer's parameters (perhaps in separate colors, like green for vertices and blue for amount, etc.)? The reason I'm asking this is because as much as I'm against having Flash's layer system in Synfig I realize it can increase productivity: we can merge the parameters with the Layers panel, in turn merging with Timetrack, so we can see/edit separate layers' keyframes at the same time.
We could either go Premiere Pro style, where parameters can be edit via Layer's drop down menu, or we can take it to another level by keeping the parameters in a separate panel altogether, like in GIMP or Blender. Similar to how we right-click a parameter in Blender and hit "Insert key", we could do the same with Synfig, though with waypoints instead. Something like this:

2)
Pose Library: What ToonBoom and Retas can do that Synfig and Flash cannot is make good use of X-Sheet to recycle Cells. Every cell in the system can be called by typing a single cell number at a frame and it shows up. Flash takes the "copy/paste" approach, and so does Synfig, but in practicality there's no real way to keep a library of poses. Yes, we
can export Encapsulation, but beyond expressions and blinking effects the Paste Canvas layer is not usable because it remains static.
An idea, instead, would be to have a
Pose Library of either individual or encapsulated layers. This parameter would function like Paste Canvas, but this time it saves
every waypoint (if it isn't there, it creates them) of
every selected layer in that frame into a namable library (say, "Walking Pose"). So this way, it can function the same way as Paste Canvas, but instead applying a set of waypoints you've saved into the library, giving you the ability to "tween" along with it.
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