Currently there is not a simple (or documented) way to modify the speed of an animation.
I think it will be incredibly useful if you include an action to modify this value.
For example, I made this algorithm to simulate the speed and time variations of each slot in a slot machine:
It’s relatively easy for me because I’m a programmer and I think in algorithms (or I’m crazy, don’t know yet) but it’s hard for some new users of this software to guess how to achieve some stuff.
The same effect I get in that example can be achieved with many less lines if an action as “Change animation speed” is created.
And as this example, I think there are other values that would be useful to change at runtime.
Those variables are there, we just need the way to change it at runtime.