I did some digging and my router, the Asus RT-AC68U C1, being Broadcom-based, has no working WiFi. Guess I'll stay put.
(I did not install it, because the model I have has fallen out of the supported hardware list a while ago, but it'd be great to hear how well it does for anyone else.)
DD-WRT and Tomato/Merlin might interest you. The latter tend to work better.