You're right, i never use Repose and Fluid Aura as WHM, but still it's not comparable to Undraw.
Since AST can only use one card at a time now, you might as well just dump the card on someone randomly, or just wait for the end of the Draw CD. In no situation ever will Undraw be of any help. And unlike Fluid Aura and Repose, you can't even use it for fun, since its only effect is to throw away your card without any animation whatsoever.
But really what bothers me the most is the fact that it's so apparent that SE just didn't care.
Even with the old AST, Undraw was almost never used, and for some reason, when they had their big healing jobs overhaul, they thought "Ah, Undraw ? Meh, let's just leave it there, whatever.". I mean, they could have easily swapped it with something more useful, or like OP said, tweaked it a bit so that it had at least some use cases (even niche ones).
