We costed all the professions - number and nature of favoured categories, magic spheres, abilities, level bonuses, etc - and analysed the spread of costs. Then we went through the professions to reduce the variation in total costs and to remove "sameness" (typically talents granting bonuses to an entire category, i.e. all Thieves getting the Subtle Talent, etc.). Harpers and Rangers were coming out too high (lots of good cats and spells) and the Harper had some sameness issues.
Best wishes,
Nicholas