There isn't much that is "niche" about the design of my forum character. An elven witch in a black dress. The only thing that is stopping her from being a Viera is their decision to ban them from using hats. I'd probably receive even more unsolicited messages than I do normally if she was a Viera.
In any case I would welcome with open arms if they remade Elezen to be more in line with Viera proportions, just as I would welcome Hrothgar fixes and a female Hrothgar that looks good. Making things that a lot of people like is generally a good thing. In any case the "match" to Ronsos in FFX are tall females with not very bulky arms. They are not bigger than a femroe.
As others have mentioned I just do not see the value in catering to a niche within a niche when there is a far more appealing alternative route they could go as opposed to doubling down on things people do not like.
It's a matter of reading the room and being honest. Most people do not want to play a race that is built around catering to niches. They want to play something that looks good, especially if it is a female character. I think my female elezen character looks ok, at least when she's wearing that dress which works with her...unique proportions. If they release something that looks bad, then they will not succeed in obtaining my fantasia money, or most people's.