Worked in technology / telecomm since the early 90's. Architect, leader, idea guy.
Answer to: Replace the wifi card with a current 802.11ac card?Actually, that QuickerTek answer is the best one (as they're planning on releasing a new version of the card - it's currently in development). Keep an eye on their website to see when it's released. No only for faster speeds, but also new Apple features use the "time in flight" feature found in 802.11AC cards to determine proximity. This is used by the Apple Watch for auto unlocking as well as the new Apple earphones (AirPods and Beats3 Wireless) - both with the W1 chip. The proximity is used by the headphones to auto-switch between devices (as well as automatic pairing through the icloud - there's likely a secure token passed).