I have extensive experience with Trikes and fairings....
My first was on a Peter Ross Trice with a ZZipper fairing,
However I found that the fairing quickly suffered stress cracks around the fittings.
I then fitted a Streamer, shared between my Sreet Machine and the Trice.
A better design, and one that allowed a little movement that increased ease of access.
When I then changed to the Catrike, I bought a Windwrap XT and this has been the best so far.
HOwever whilst this works well fo warmth and comfort it is not as protective as the Streamer, so I have invested in a Windwrap RX for winter use as it has more coverage.
In summary....
Fairings are good at looking cool, raising temperature (much warmer) and weather protection. They also make a difference in performance.
However they can restrict access and egress from a trike, and if too high can limit visibility.
Light mounting can also be an issue as you need to mount outside the fairing as otherwise the light illuminates the fairing and this has a two fold effect. Firstly it means that you have a large bright object in front of you that reduces night vision, secondly it filters the beam, attenuating the brightness.
This can be an advantage though as it does increase visibility.
You need to make your choice and decide what you want.