Suppose Slavery civic is at Masonry instead of Bronze Working.
1. How would it affect strategy?
2. How would it change game balance?
3. Would you like it to happen? Will it ever happen?
Interesting idea.
My first response is hell no, it overpowers Masonry. Then I started thinking...
Masonry offers: Walls (well, good for using slaves), quaries, Certain Wonders (pyramids/Great Lighthouse/great Wall perhaps another or two I am missing), required to tech monotheism which founds Judaism and opens the tech path the Theology (Christianity) and the AP. THAT is an aweful lot for one very early tech (you can get it off mysticism and/or mining), so almost any CIV can tech it early (at least the ones with the mentioned 2 techs), and FASTER than BW
BW offers: Axemen, shows copper, Slavery civic, chop forrests. LEads to iron working, otherwise a rather dead end tech.
My point is that Masonry opens up alot of the early game, while BW has some very powerful specific uses.
I understand the idea, nerf BW a bit. I am not sure where it belongs but I think Masonry would foul things up a little. The only way it would work is to increase the costs of Masonry to tech while decreasing BW, but that will imbalance military too much.
So I say, keep it as it is.