Toi — What better role model can there be for a potential BT then someone who is also growing in their avodas Hashem? Obviously we are not talking about saying “I don’t like that one”! But what kidn of “disastrous effects” will come if, to use the example of the OP, you are learning Hilchos Tznius and share some of your own personal struggles, in line with “this is the Halacha, and it is what Hashem requires of us. Unfortunately I have a big taava with regard to wearing skirts that are “borderline” Halachically. I know it’s wrong, but I find it hard and I’m working on it.” You are showing this potential BT that even FFB’s have their nisyanos that they struggle with. Why does this “destroy” yourself as a role model.
I am not a BT, but the people who have been the biggest role models in my life were people who I had a close enough relationship with to sometimes see their flaws and how they were trying to deal with them. No one is perfect, and pretending to be so will not bring people closer to Avodas Hashem.