The MotoWpNoMo and SlapMyMoto vulnerabilities were patched in 4.4.2, so if you updated to 4.4.2 on a locked bootloader you lost what MotoWpNoMo gave you and write protection is enabled on your phone. But you might have kept root.
The OTA's do a pre-flash verification check. Things like Xposed, patches, hacks, modifications, etc. can/will get in the way of that, preventing the update from installing.
Also, the OTAs on the X are incremental. So if you want 4.4.4, you'll have to be on 4.4.2. If you want L, you'll have to be on 4.4.4.
If you really want future updates, you have to weigh how important Rooting, even partial or temp root is. (Temp root means you have root until you power off/on your phone. It still doesn't disable write protection so you can't create files in /system and other folders, and any changes made would be lost at power off/on)
Since you can not unlock your bootloader (unless the China Middleman can come through for you, see the thread in the general section), you can't even temp root 4.4.4, and likely wont be able to L.
If rooting in the future doesn't bother you, the quickest way to get back on the OTA path, undoing any changes you might have made, is to use RSDLite and re-flash the firmware which is currently on your phone (NEVER ATTEMPT TO DOWNGRADE or use an older ROM version!! or you risk bricking your phone!)
As for battery... it could be an app, like some of the recent google or moto app updates that have come down recently. It could also be the battery in your phone degrading. There is a thread on battery life with many good tips. And you could try running your phone until it shuts off, then charging via wall charger until 30 min after it says 100% a couple of times in a row to reset the battery's "electronic battery gauge".
As for safestrap, I don't use it since I have a Dev Edition and unlocked my bootloader. There are some threads and discussions over on Rootzwiki.com BUT you will need to be rooted with write protection disabled to use SafeStrap... Since you are now on 4.4.2, you can't disable write protection, so safestrap is out.