Matt,
Yea nobody in the Mopar community is looking for a high performance 14" tire. And only some of the A-body guys would even acknowledge that the cars that came with 13" wheels.
A 50 series would look goofy to me on my '68 Barracuda. When building the car I aimed for what's probably considered a traditional look. Not to mention PA roads are hell on wheels with less than a 60 series tire.
I have to admit the Mickey Thompson ST's I put on it aren't bad for an S rated tire. For some reason they decided the 225 didn't need raised white letters but the rest of the line gets them. So I had to go black wall this time around. On the black car the tires get lost. It needs either RWL or a stripe on the tire to break it up.
I'd love to trade off a good bit of the tread wear for grip since they will dry rot long before wearing out. Don't worry, my suspension hasn't been stock for a long time. 
For my car, if it gets any serious handling use at a timed event I'll put together a track set of 17" wheels and contemporary sized tires. No different than bolting up the slicks for the 1/4 mile. Just more stuff to store. Which is its own headache...
Well, everybody knows that the bird is the word!