How do I enable a keyboard OTHER than Google Keyboard via ADB?
I managed to solve this. To make AnySoftKeyboard my main keyboard, I had to:


Turn it into to a system app (with Link2SD)
Reboot as instructed
Put the following commands via ADB:


adb shell settings put secure default_input_method com.menny.android.anysoftkeyboard/.SoftKeyboard

adb shell ime enable com.menny.android.anysoftkeyboard/.SoftKeyboard

(I put both just to be sure, but I think putting only the first command will work fine)


Uninstall Google Keyboard (with Titanium Backup)
Reboot just in case anything had yet to be sorted out


And done.

The most important part was making it a system app, because as a user app it would either:

a) not be the primary keyboard after a reboot

b) flat-out refuse to function (even if it was the only keyboard on the device).