Bump, any advice?

 

An 'unconstructed jacket' is one whose outer fabric is cut basically like a regular suit or sport jacket, but which has little to no canvassing or padding, as you said. They are often said to feel and fit more like wearing a cardigan, and usually use softer fabrics with more texture and drape as opposed to a substantial crisp suiting fabric.

A 'shirt jacket' appears more like a shirt in cut - usually a shirt type collar and cuffs, higher buttoning, etc., but meant to be worn untucked and usually more substantial than a shirt in construction.

https://www.styleforum.net

 

Ah ok, that clarifies things. So since there's no canvassing and padding for the unstructured jacket, I expect the labour hours needed to make one is significantly less than to make a normal suit jacket. How much less can you expect from a tailor to make an unstructured jacket as opposed to a suit jacket?

 

unstructured jacket = "Miami Vice look"

In a suit jacket, I would draw the line at "natural shoulders" vs. "unstructured". Just my opinion.