I started using the trial version of Rhino 9, and I wanted to ask if other users have experienced the same issue as I have.
While working, I noticed a slowdown in my workflow: I have to waste time looking for the arrow to increase or decrease the size of the curvature graphs.
Have you noticed it too?
Dear @Fabio_Bau welcome to the Forum.
There is no automatism for the display scale value.
110 to 120 are typical values for consumer goods-sizes.
if you build a railway-track with a radius of several 100m you might need a much higher value.
you can also type a value in the field next to the 
rhino should remember the value next time you use the tool. kind regards - tom
Those tiny arrows haven’t actually changed, but the big Plus and Minus for adding/removing objects kinda look like they should be for changing the scale.
V9 appears to be using a new pardigm for command panels, with the plus and minus icons used in multiple panels for adding to and deleting from the selection. Several other icons are harder to decipher. As with any paradigm in is obvious to those who know it, but may not be obvious without sufficient experience.
And pretty much everything it’s used on has some sort of a “scale up/down” control on it, that’s way harder to hit.