ZyXel Keenetic 2

What firmware should I install on Zyxel Keenetic?
cpu - MediaTek RT6856 700MHz
ram - 128 Мбайт DDR2
Flash - 16 Мбайт
Wi-Fi 2,4 - Ralink RT5392 2T2R/300Mbps

What does the ToH say?

the silence in the ToH isn't surprising, as the whole SOC isn't supported - and most likely never will be.