Something really non-intuitive that I had to be knocked upside the head with while tanking TfB: go into your Preferences and find the camera control for how far out you can zoom your camera and put the slider all the way to the right. This will maximize your ability to zoom out.
As another commenter said, tunnel-vision can be a huge issue, and the default field of view is just not wide enough, in my experience, to be able to keep an eye on everything. I can't play with it all the way out like the person I tank with, but I have found that for my personal base state I like it to be a little farther out than game default.
For sure. On TFB last boss seeing the adds come in, where the sput is, where all the different things at play are is key. More so if you are calling things out in a raid.