I have a fairly narrow foot with a medium high arch and these fit well straight off with no aftermarket insole or any other adjustments.
I have a similar foot and love the Northwaves for their fit. I'm on my third pair. They do pack out a bit, but not so much in the length. I wear a 10 to 10.5 shoe and a 10 Northwave, so pretty true to size. Well made boots, the two pairs I've replaced have been due to becoming too soft after 4 years, but not one broken stitch or burst seam or popped eyelet.