SuperSU Root & TWRP Recovery (XT1096)

Thanks in advance for any information/guidance provided! Please bear w/ me, I am pretty new to all of this. I apologize for any incorrectly used terminology.

I have a Verizon Moto X 2014 (XT1096) that I have recently unlocked the bootloader and rooted via SuperSU and TWRP Recovery. When I opened SuperSU, I got an error message stating that I needed to update the binary, but it was unable to be done OTA. I used TWRP to sideload the binary zip file onto the phone's internal storage, which seemed to work fine.

Using the same method, I moved CM13 (01/14/16 nightly build) to the internal storage and followed the remaining steps in the process.

Jump ahead a few days (phone seems to be working great & am running on T-Mobile LTE perfectly) and now I have a few questions:

1. Is my phone for all intents and purposes, considered Pure Edition since I have unlocked BL and rooted the phone?
2. I can download nightly updates, but when I try to install them, the phone reboots/does not install the build.. How can I download and install the updates OTA?
3. Is it necessary for me to keep the TWRP recovery/backup zip file on my phone's internal storage? (wondering b/c phone is ony 16 gb and the backup used a large amount of available storage)
4. Is there any way for me to have stock Marshmallow on this phone instead of CM?

Thanks again and sorry for the likely horrible explanation.

Daniel

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