Oh, me too -- but it smacks of complaining that there aren't enough Warforged in Forgotten Realms to say that the Blood War is broken when taken out of context
Or, more accurately, not enough Changeling in the Forgotten Realms. They fit, it's pretty natural, and while it doesn't work *exactly* the way it was initially presented...
... I think that I like it *more*.
Especially if (kshhh! broken metaphor!), as I suspect, the Prime is the best connection between the Hells and the Abyss.
Then most of the fighting can occur on the top layers of the respective planes, with important strategic operations on the Prime. The Blood Cold War, sorta. But you could play it the other way, too; just have a connection of some sort between the two fiendish planes. Blood War + Plane of Battle tying together the two. It doesn't need much fleshing out; it's a place that exists solely to let the two duke it out, and is home to the yugoloths.
I've never liked Yugoloths, or Slaadi.

Forgive me, please!