I hear what you're saying (even if nobody asked :D ) but you have to hear something: Not everyone just wants to go to car shows and the drag strip.
We each have a vision for our cars and for most of us, we do the best we can and get there step by step. I have wanted to make my Dart into a competent handling car since I got it when I was 17 (23 damn years ago).
An A-body isn't a terrible place to start for a handling build. They have some limitations but their simplicity, well engineered suspension design, relatively light weight offer some respectable potential and it can be done without drastically altering them away from being the lovable, honest, practical 60s/70s cars that they always have been.
You say "lumber wagon" in a derogatory way but maybe you don't appreciate that there is a reward for giving up plush driving comfort. Stiff/rough ride is fine so long as the car turns-in and behaves in a way that justifies it. I know the second part is achievable. I'm just not there yet.