I know skill checks depend on the stats of the attacker and the defender. I think it would be helpful to show players in game estimative chances for everything based on some default values of what players could expect their target to have.
For example showing chances to inflict statuses (including the list of them in a tooltip or something) against a target with a typically low amount of willpower/fortitude and the same against medium or high amounts that we could expect other players/monsters to have. Stuff like that would be incredibly helpful to see at a quick glance how your character build is doing in a vacuum. And then you can ask other players how much they actually have and get an idea of how well you do against that currently. It would allow more control and an easier time making changes with builds.
That kind of stuff is important for player retention too, as not everyone wants to or will open the wiki when just starting in order to understand the basic mechanics of how the game works. I think it would help the game do well.