This is mostly because the 2 passanger seats in the demos. Place a ranged class in them and they suddenly make it near impossile for others to attack it, especially if they continue to roll on. With the boost to damage from 4.01, this has become an even greater advantage.
I suggest the passanger seats be removed/inactive in Strand of the Ancients. Doing so would definatly balance the playing field for all classes and make the game dependant on overall team work and skill comparedto right now where all you need is 3 or 4 ranged players in demos.