I think cutting through the fluff, what they're really trying to do is capture refugees from other games or new players who feel put off by the lack of a bestial race, probably because an analyst in the company suggested this is a demographic the game is currently not capitalising on. It's an uncertain gamble, though, and existing stats on these races both in XIV (closest proxy being Roegadyn) and in other games don't exactly inspire confidence - even if you just look at the raw numbers and ignore the reasons as to why some bestial races enjoy a degree of popularity, there is nothing at all to suggest male Viera would not end up being the more highly played of the two.
Now, I don't exactly favour diversity for its own sake, but I'm struggling to see 1) how the Viera females fit the "fierce warrior" archetype and 2) what they're adding exactly. I agree that the rationale for not adding male Viera on either of these points is paper thin. If they failed to make Viera males look adequately different or fierce that'd be a failure of imagination on their part and nothing inherent to the race as an option.
For female Hrothgar, there should be enough ways to avoid making them look like tanks but still retaining a bestial look, like this art:
