Graphic failure/FPS drop

TL;DR - Graphics fail to load at random times, FPS drops from steady 50+ to 15-20.

While playing the game, some graphics will either fail to load and instead load their pastel polygons, or they will just fail to load all together. The latter is especially cumbersome during boss fights in the instance the boss model does not load. When this issue happens, it causes hard game lag, loading lag, and, in some extreme cases, hard crashing with no specific error message. During this lag, frame rate plunges to below half the normal rate, "normal" being the average frame rate during typical play, including standing in populated areas, loading into dungeons, and overall environments and surroundings.

This issue has been happening since the maintenance on 12-12-16. I have reached out to customer support for the graphics card and they have suggested reaching out to the customer service for the game instead. I had a chat with a representative and they suggested posting here. If there is any information I forgot to mention, let me know. I hope this all helps out.

Troubleshooting that has been done thus far:

Driver rolled back to previous version
Using driver uninstall tool, uninstalled current driver and reinstalled previous version
Using driver uninstall tool, uninstalled current driver and reinstalled latest version
Starting with minimum graphic settings, gradual increase of settings in attempt to isolate problem
Complete uninstall and reinstall of FFXIV with patches
Removed, cleaned, and reseated graphics card
Removed, cleaned, and reseated RAM
Monitored graphics card using stock program included with driver to check for heat and voltage spikes
Reverted all possible settings to default values on graphics card

System information that might be helpful:

Windows 10 Pro x64
AMD FX 8320 Octo-core ~3.5GHz (Not overclocked)
16GB RAM
DirectX 12
AMD Radeon R7 360 with driver 16.12.2

Current FFXIV Settings (DirectX 11):

Full Screen 1920x1080 (60Hz)
Enable wet surface effects [Yes]
Disable rendering of objects when not visible [Yes]
Use low detail models on distant objects [Yes]
Real-time Reflections [Maximum]
Edge Smoothing [FXAA]
Transparent Lighting Quality [Normal]
Grass Quality [Low]
Parallax Occlusion [Normal]
Tessellation [Normal]
Glare [Standard]
Map Resolution [High]
Shadows [Display All]
Shadow Resolution [High - 2048p]
Shadow Cascading [Best]
Shadow Softening [Strong]
Texture Filtering [Trilinear]
Antisotropic Filtering [x4]
Movement Physics [Simple All]
Blur the graphics around an object in motion [Yes]
Screen Space Ambient Occlusion [Off]
Glare [Normal]
Enable depth of field [Yes]