@sapphire @skylar @icon_of_computational_sin >the router lives in a metal box in the basement, that's a terrible location for a WAP
Acquire some long antenna extender wires and run those wires to a better spot and put the antenna's there?

>good luck finding a card that works acceptably with any network with more than 2 wireless devices
Atheros 802.11n cards, especially the tri-band ones work great.