We have a guide (hunter/strider) for a caravan in our party. The areas we travel doesn’t really have forests. Can we safely exchange Forest-wise to Wilderness-wise or something more thematic as long as the new wise isn’t to powerful?
Wilderness-wise is a pretty broad term, you could go with something along the lines of hiland-wise or plains-wise and that doesn’t appear to break the flavor of the characters. I personally would ask the PC playing that character. Why do you have Forest-Wise? What part of your life was spent in the forests, and why have you left that area? That way you get more depth to the character.
The short answer is yes. If forests aren’t applicable that’s a simple modification to fit your world. Purists might complain but hey, it’s your game, and useful wises are much more fun than inapplicable ones.
The also could have Appropriate Terrain-wise and it would work. Or Wilderness-wise; it’s broader but I don’t think it’s too broad and it’s a fine thematic fit.
I’d avoid changing it unless in your setting the Striders really do patrol some other type of terrain. Not everything in chargen should appear to have immediate application.
I say this having played a Strider in a game where we did START in the forest, but the intent was to be out of it within a session or two, in fact, I took it as a wise for a specific forest.