I won't debate against strong arguments.
That is up to you, even though you are theoretically supposed (and always invited) to do so. It's definitely better trying to argue your points with your own words whenever you have the possibility to do it; you would otherwise leave the discussion to other people, who can't obviously answer precisely on your behalf and back your thesis as you would like to.
In this case, the lore arguments are quite clear on the matter, though they don't actually exclude it completely: we know that female Dwarves do exist, and the fact that one of them could become a warrior (as a very rare exception) wouldn't be, in my opinion, more at the lore's ends than concepts as Helegwen and the lore-masters currently are (and I think that Helegwen was indeed a great legitimate addition).
So, I would say that what would be really required is the actual will of developing such proposal and the relative time to spend (something quite improbable now, I guess, with other fundamental priorities). Besides, just to give a hint, what about proposing a completely supportive role for this hypothetical heroine (that is, pure support as Erestor's abilities)?