Tbh I didn't think it was that big of a deal for her to be able to use it, I mean why would Hashirama be the only ninja to have that element?
Just because she has Mokuton doesn't mean she's about to use a thousand hands Buddha or anything...
I wish it had been one of the new Gen of ninja though rather than Moegi, I'd like to see more of the wood release, or perhaps one of the other elemental Kekkei Genkai, such as steel or dark release, or even just see Ice Released used in different ways other than the mirrors technique...