I connected the Asus RT-N12 router in "Repeater" mode, and placed it in the room's high point, about 15 feet closer to the Blu-ray. So far this solution is working very well. Looks like I picked up 7-10db at the DVD player (ran about 15 tests over a 2 hour mid-morning period), and my smartphone.
Netflix loads noticeably faster and there is no buffering. Stream speed at the player is now about 2.1MB (vs. 1.2MB a week ago).
Thanks all for the ideas. We'll see what happens over time, and whether during Netflix evening prime time there is deterioration.