I never said I would not cast another archer skills after I used Multishot, didn’t I? But you did assume that Wizard players won’t deal another damage for 108 seconds with your statement. 
Then tell me, what would Archer players do if Wizards can have very similar, same, or even better damage than Archer?
Ask IMC to nerf Wizards? Or change their class to Wizard? Or stop playing while whining to the developer on this same thread?
That’s why, in order to make things more “balanced”, Wizard’s skills have longer cooldown than Archer. They may not have the strongest damage for a long duration fight as you said, but does it really matter? Wizard is not a strictly damage dealer class in the first place, different from Archer. Imagine if Wizard can do CC and deal damage as strong as Archer with short cooldowns, people will abandon Archer.
And I stand by my point that Wizard still can compete with Archer in terms of damage. Even you have admit yourself that in the first 18 seconds or more duration, Wizard will deal much more damage than Archer against a boss.
Even if the boss didn’t die right there, the amount of damage Wizard can contribute to the party is still considered very high. That’s all that matters.
This would be my last reply to you as this is really going off-topic.
@cloneart123 you can still play a DPS Wizard and do great, However, don’t forget the design of the class itself doesn’t force you to be a strictly DPS class. Just because you take Thaum c2 or c3 doesn’t make you a support class because you can still take classes like Pyromancer, Warlock, etc. The Thaum’s buffs will increase your damage potential even further. Never compare yourself with Archer because you are a different class with a different role.
And as a Swordsman player, I would love to have both Wizard and Archer in the party. Especially Wizard, since they have tons of AoE damage and synergize well with Peltasta’s Swashbuckling.
When you use both, people who attack you first will get hurt from your revenge sevenfold first.