So... bringing this back to life. I abandoned the powerline adapters a while ago. I don't know that it was a problem with them directly and I have reason to believe that the outlets in use between my upstairs office and my wife's office downstairs were on 2 different legs of power coming into the house. And that switching between the 2 caused pretty consistent drops in internet access.
So fast forward to last week and my wife has been complaining about the internet on her computer again... constantly slow, constantly dropping out completely. I had her on a highly rated USB adapter that did ok but I know that I've been sitting 10 feet from her on my work laptop and I didn't notice the same drops as her. So I decided to try a new adapter. This time, I decided to go internal:
https://www.amazon.com/TP-Link-Wireless-PCI-Express-Archer-T6E/dp/B016K0896K/ref=sr_1_12?ie=UTF8&qid=1479136628&sr=8-12&keywords=tp-link+ac1200Got it on Saturday and she was working a lot yesterday and said it was much better. Consistent speeds, no drops. It was reporting only 62% signal but it called that 'excellent'. I'm going to try and move things around to see if I can increase it, but frankly it's working so well I don't know that it is necessary. Speedtest showed roughly equivalent numbers to my hardwired PC upstairs so the signal strength must not be affecting it.