Would that really be the fix, though? I agree that Skull calculations sort of throw up their hands when the board gets full and go, "Okay I don’t know anymore but basically this one dies," but the justification for Sheggra’s nerf so long ago now was as follows:
The bit about “EVERY time was the right time” rings true for Bone Dragon today in endgame play (and Sheggra’s nerf was about endgame play, the scaling with Magic was no problem for leveling). There’s no strategy to his spell – you use it as soon as you can, the only thing to be “careful” about is if the enemy has already been stripped of armor.