Rancor sees the ARF trooper the same way that other battalions see their standard trooper, which (in at least 2 cases that I know for sure of) are not used or have already been replaced with a different whitelist. The ARF trooper is not the only whitelist we have that no one uses. We have the ARF Trooper (our basic trooper), Rancor ARC Trooper (ARC with no regiment, so just the ARC kit), and the Rancor Officer. The thing we are looking for is to have the same that other battalions already have available to those that are not in subunits.
This suggestion would stay up if the subunit gets denied, especially since we wouldn't know if the subunit suggestion was denied until after suggestions are closed. I understand that if the subunit suggestion gets denied, this one might be as well.
If a player for some reason went from ARF to ARC, but stayed in the same regiment, they'd still be in that regiment. The goal is to allow for a better new (or new to Rancor) player experience, as well as for those that are not ARC trained.
"You don't need extra stuff for people who plan to leave that position every single time." - This is already the issue with Trauma's unit. As someone else said earlier, it is used as a step ladder, a place holder, something to do until a player becomes ARC trained. While you are correct, we'd have people who would ultimately go from ARF to ARC, but they wouldn't be taking away from the subunit that doesn't fit within the battalion. I will also point out something you said earlier: