Your games, with very high likelihood, are always filled with premades on every side. The thing is, that the overwhelming amount of them are "just here for xp". That's why a single premade of "actually here to do PvP" players has such a massive impact on games. Removing the option for premade queues (and more importantly, a more randomized approach to fill alliances to prevent queue syncing) would reduce the impact, but the outcry from the playerbase would be sizeable.