(I don't recall if this was proposed before, nor I can find it on the forum or on the Discord)
Currently, the only way to assign a crew to a craft is from the crew screen of said craft. The inconvenient is the screen doesn't show the armor a soldier is wearing.
On the other hand the Armor screen shows the armor and allows the armor assignment for a soldier, but if you want to assign a soldier to a certain craft, the player needs to remember said soldier name and go back to the crew screen to select them.
My suggestion is to allow the craft crew selection also from the armor screen of the craft. Maybe using a combo, such as SHIFT+LClick, or something similar. This way, in a pinch, the player can select soldiers based on their armor directly from that screen.