Designing Path Racer/Porteur Frame - opinions?

I meant the opposite really. I have an old steel frame with quill stem and I like it however if I were to buy a modern frame I would look for superior tubing (ie better than 531) and Ahead, whis IS better than quill.
I'm not having a go at your project, I just believe you shouldn't dismiss modern technology.

Yeah, I may go with 631 tubing instead. A-Head is "better" marginally, but Standard Quill looks so clean and nice, I can't compromise on that one.