Oh, bad times. That's a nasty combo for a tight corridor! Arcane Sentries are probably the most evil elite ability around.
As for crafting, I think it will have some utility for future playthroughs, filling in the gaps as you level new characters. But yeah, with the AH I suppose it was unlikely Blizzard would make crafting too useful in the late game. Still, it would be nice if in a patch they added at least a couple of mindblowing smithing recipes to loot drops.
