My Personal Take
King is a Secret tower. Instead of Damage being his main DPS, it summons allies to fight for him.
Even though it's a secret tower, it is very underwhelming to say the least. With it only having 2 placements and the max hp of its summons being Queen, who has 5k hp.
But a big problem is that enchants don't affect the summons at all, not even the HP.
To make the tower better, it should probably be reworked just a bit. Like the summons HP and how they work, like knights doing slash attacks, or adding archers that shoot arrows, and instead of Queen, it's Royal Knight (because why would a queen go into battle), and with increased hp. It's basically a weaker version of the king (the enemy) where it swings its sword.
Comparison to other secrets
I think the least amount of placements it should have should be 3. Considering Juggernaut has 5 placements (more than double what king has).
And all juggernauts placed down is 22k+ DPS (With apex)
I'm not saying it should be as good as juggernaut but I'm saying it should still be able to compete since it is still a secret.
More people would rather have Juggernaut than King, which says a lot with how underwhelming he is.
It would be really nice if he got a few buffs here and there. And maybe a placement increase would be nice.