Hmm, that's an interesting point to ponder. I don't really see the three oaths going away completely so long as the White Tower is around, so in the same vein, I can't see them being modified. But there are a lot of other female channelers out there that do not take the three oaths. Also, if...
For the in-book question, I'd assume the 4th age will once again have power-wrought weapons, now that the ability to make them has been rediscovered. Power-wrought armor would be pretty awesome, I agree.
For questions about real blacksmithing, maybe check out the hand-made crafts forum? That's...