How to mount sdcard1 (external SD) as internal storage? I understand that there are many tutorials and the like on this very subject, but none ever really matched my exact situation...
   I have a rooted moto g in which I have a 200gb micro sd card (laptop is down right now, I download all my media with my moto) and a mere 5gb of internal storage.   Now it becomes confusing for me... my storage folders are named 0 and 1, internal and external... and my "internal" storage is labeled as"emulated" sdcard0.  If I enter the sdcard shortcut from my phone's root directory I'm taken to this emulated SD.
   So, okay, I'm assuming that my internal storage is partitioned in two, perhaps the first partition is dynamically allocated so I have a place to store my pics and downloads at the same time maintaining the files in /data...so now I'm stuck constantly moving files from internal to external every time I download something because I get  insufficient storage warnings.  So how would I go about dedicating the 5gb totally to my /data and having the phone then make my 15gb sd take the place of emulated sdcard 0?
Due to how Android handles SD card permissions, it is no longer possible to "swap" the internal and external storage of the device and trick it to use the SD card as "internal" storage any more.

Since you are rooted, I would look into any of several Android 6 based ROMs that are available for the Moto G, after installing one of those you can adopt the the SD card as internal storage. Be aware that this will make the card unreadable in other devices without reformatting it and it can only be seen via a USB connection since it will be formatted as ext4 and encrypted. I would recommend using XDA's Moto G forum area for more information regarding specific ROMs and how to flash them. 

The other option would be to use an application like Link2SD, which would require you to partition and reformat your SD card, and it uses symbolic links to the partition on the SD card. This still requires the app be installed on the device first and moved, but it can free up significant space and using the paid version can move even more data to the SD card. See the application linked above for more information.