I wouldn't think the direction of the antenna would matter much when two feet away. Is that a thing?

I've definitely heard about people having problems with wifi on their Chromecasts. I could have sworn that some said there could be issues if the Chromecast was too close to the AP.

Dan, if you don't mind me asking, how spread out is your house? You might find out that you don't need multiple APs if you have a good enough router. I've been seriously impressed with the OnHub's range, and I know that deep down you want to go all Google