One critique that I actually agree with is that there aren't enough examples of difficulties for actions. Specifically, for non-contested actions (those against the environment). I recommend that either in the expansion or in SA2, a list of example difficulties is included.
I'm starting this thread in the hopes of reaching some sort of consensus as to how difficult various tasks should be, at least in cannon.
To help, I've done some math.
The following table lists the average roll given a single die and capability, where the player is willing to spend a specific amount of reserve. This table assumes that the player is attempting to achieve the highest average result (so they're re-rolling on a 4 or less and adding 1 on a 5+). It does not take into account modifiers like CVs, using the wrong profession, or having help. It also doesn't take into account the other die being rolled, although that is more relevant when the player isn't spending reserve (or is spending very little).