Honestly, I don’t believe in overused FCs in roleplays. The whole point of having an FC is to have a reference for what the character looks like, so players can visualize it in their head as they roleplay. If an FC is used often, it doesn’t really matter- it just means that they are well known and physically appealing to most people, and the admin figured they’d get more auditions for a character that had that FC. As long as the bio is original and not overused, then I don’t think it should matter what the FC is.
As for Rachel, I adore her. So I would highly encourage you to use her as an FC in your roleplay, overused or not (I do believe in underused FCs, just not overused ones).
Underused FC: Jessica Parker Kennedy
Underused FC: Holland Roden
1/100 Narnia cast: Anna Popplewell
The fact that this gorgeous girl is so underused absolutely astounds me.
Of course! Not all of these are necessarily in their teens, but they could pass as teenagers and I honestly don’t see enough of them:
Hope this helped!