Quick Question: Subframe connectors- WHY didn't they do this from the factory?

Uh, the whole point of unitized body construction is NOT TO HAVE A FRAME.

I find it incredibly fascinating that the engineers were able to use laminated sheet metal and carefully designed and placed torque boxes to support the twisting force of 440's and Hemi's.

Mopar was way ahead of the curve on this, and after their example, almost 99% of all cars adopted uni-body construction.

Chrysler still had the superior design, well into the 70's.
Have you ever looked at a camaro or nova front subframe?
YIKES!