One nice option in the game is being able to switch roles.

We can all grind the warior/str/greatsword(or maybe sowrd and board!) route as primary.

But on the same toon, everyone can also switch roles and grind out another role as secondary once the primary toon is specced out. Not only would the secondary grind be less due to some tagential stat and skill gain(common skills for example) from the primary role, but in the endgame, the clan as a whole will be more flexible because we can have folks switch roles as needed to maintain class balance in the groups.

The key will be to figure out which primary roles and skills are congruent with which secondary roles and skills. For example, a warrior/skirmisher might be best using sword and board with a bow for ranged attacks. a warrior/elementalist might use greatsword and staff...