You’re basically saying you want there to be an incentive to keep these premades from trying to bypass such a limitation, yeah?
How?
In Russian realms for example (retail), it became a social hierarchy based on how many HKs you’ve got on a character, even though it was meaningless in the game. This alone kept them from sticking to RBGs for a challenge, to actually prefer stomping pugs in the unrated matchmaking pool.
However even this isn’t as popular as it used to be for many years, because many of them grew tired of it.
Germans were infamous for turtling in retail BGs, doing the same premade trickery as seen now. They didn’t do it for the HKs in the same sense that the Russians did though, it was just for the sake of winning. Just for that difference in the loot box at the end, and a little more honor points.
You’d need a way to completely remove the motivation to perform the premade trickery for it to work. Which would make the non-premade queues too meaningless.
This doesn’t work, it’s literally the same thing that has been used in AV now. Basically, with the trickery to create premades, why would premades aiming for more honor choose to only face other premades when they can do the trickery (if the circumstances allows it with the pool-size), to only farm pugs?
It’s the chaos that keeps it fair in the end. And the setbacks serves as a social motivation. As simple as that.