Shoulder pads are needed for the jacket to hang right.
Lining up the stripes from jacket to kilt would be next to impossible because the stripe at the top of the kilt will be smaller because of the taper.
Cotton seems to be an unusual fabric for a Jacket or anything dressy. It just doesn't behave like wool. Wool is easier to sew and to have things line up because it will move. Cotton will show wrinkles faster with every wearing. The bias tape sounds like it would look like a costume instead of a nice kilt jacket. I would do a regular hem instead.

Sounds like an ambitious project (one I wouldn't try without a pattern). Good Luck and post a pic when you are done.