The idea is one of the most powerful builds.
Double wands works when you have at least 3 point in dual wepon and one point in wands. Its lots skillpoint. Start investthere after 6th level. 1-6 level you get just one skill point per level. e.g. you would need dump all your points there to overcome barrier. Which makes your character pretty flat.
In first 6 levels put points to magic skills rather. And other skills (Will, Bodybuilding) Dont use wands for attack. Only for spells. This way you get a versatile character. Remember first point in any magic school has best reward. Only Hydro worth 4 skill level because of Hail. Focus to get spells Witch - Low Will and Charm. Those two spells combo is badass. Two mages in group which both of them uses this combo in first turn that is like a cheat.

After the 6th level, dump all point to wands. To get power of Wands. 5th skill level of dual weapon gives attack for 3AP. Which is insane. Consider, 15 skill points to get there is a lot, you will not have much points for traditional spells.