Can I freeze/remove com.android.keyguard if I don't use the lockscreen? What is exactly com.android.keyguard?
Is it just handling the lockscreen?
If I set my device not to lock when screen is turned off, can I safely freeze/remove com.android.keyguard?

I'm using a galaxy nexus with cyanogenmod 11 (kitkat), trying to lower RAM usage.
com.android.keyguard runs your lockscreen, home button, and a few other things I can't remember.

It's an integral part of Android.  Don't remove it.