Development of a Wizard hero from the Haven faction.

Of course, it's possible. There's an option to do this when transitioning between reputation levels. I made my cleric a Confessor at level 16 and reset unnecessary skills.
According to the manual, this option should appear at levels 10-20, but it doesn't work that way in the campaign :(

I wonder if it's possible to reset talents when changing reputation for the first time.