Nah, I don't think that would fit his character (unless at the end of a path). Part of the reason Andras and Jezera 'trust' him is exactly because he has no magical powers. In that sense, they might consider him a potential threat, but not one that could instantly inflict harm on them. Their relationship would change if Rowan got concrete power. I think that would also take away from his person as the 'unnoticed one'.
It would be much more in his nature, good or evil, to ally/manipulate himself with people who have such power (like Alexia!).