Due to an update of an Xposed module, I had badly corrupted my systemui. The phone was totally unusable, and I could only press the OK button notifying the stopped event at startup.
Lucky me, I still had not updated to 4.4.3. Via Skipsoft Android Toolkit I updated to the last Android release, and my systemui got fixed. I did not choose to perform a complete wipe, so I actually maintained my previous apps. In relation to root, I did not loose it, but I had to reinstall SuperSU to get the non-official apps working again.
I hope this helps somebody else in my same condition, with no need to do a system wipe!