The fact that you consider adding walls in the Industrial Age relevant standardizing, seems testament to the extreme of your principles (it's an even better example than 140w Manors being standardizing). That's not to say it's technically wrong, though!
I don't necessarily consider it "relevant" standardizing, whatever that means, I just think it's better to use existing unique civ features to reach the same goal. The goal, I thought, was to make it harder to raid Sioux in the late game. I'm assuming that is the goal, since you've had plenty of opportunity to correct that now.
Did you miss the part that says "Industrial Age", or did you just pretend like it? Obviously, the goal is not to make Sioux impervious to raiding.
If I had missed that, would I have posted this:
If we need Sioux to be better able to defend their base from IV and on, then we should find other, non-standardizing ways to do this like giving them a tech that allows vills to garisson into teepees or greatly buffs vills' stats when near teepees.
It was Hazza that mentioned Sioux would be "unraidable", I was working under the assumption that he was also talking about IV+.
