Similar to Streak-Breaker requests for 5*s in LTs, I think there should be some sort of Streak-Breaker for Bonus Heroes.
For example, if you’ve done 9 pulls in LTs with no BH, then your 10th pull should have a guaranteed BH if it’s a 4*.
I just say this because there have been times I’ve done 20, 30 or more LT pulls, with no 5s and no BH, and that feels very sad. I know that odds don’t improve with additional pulls (it’s the same 15% 5 and 5% BH odds with every single pull), but a streak-breaker would be something nice to look forward in order to guarantee that there’s a reason why I keep doing this.
That’s what I like so much about token vaults, and why I think those did it correctly. Token vaults constantly improve your odds, the more pulls you do. So if you pull ten 2s from a vault, then you’ll have better odds next time that you’ll actually get a 3 or a 4* (or even an LT).