In Great Sewn Clothes, there was an article called The Garment Within The Garment: Why Couturiers Love Underlinings And How They Use Them. It was another great article. Is it my imagination or has Threads significantly simplified over the years? These articles seem more thorough and advanced although I can't really say for sure because I rarely read the magazine anymore.
ANYWAY... since I haven't done a whole lot of fashion sewing in the past twenty years, anything more than a serged seam will be a "step up" for me. My goal is to create a jacket that I'd wear so it needs to be soft and comfy and I want to finish it relatively quickly so it needs to be less labour intensive without a lot of handwork. I've decided to layer the fashion and underlining fabrics paying careful attention to aligning the grainlines and stitch them together by machine first. After that, my goal will be to make the inside as neat and interesting as the outside.
I've done samples of Hong Kong seam finishes but have never used them on a garment. I think that's the direction I'll go in. The majority of the work can be done by machine and I will get an opportunity to try new things and to take my work just a little bit further. And later, when I take the jacket off or it flips open, it'll be a flash of fun.