We keep asking for a "refined" body model for a long time only to be ignored or take the "memory limitations" excuse as an answer. Or the "we have no plans for this at the moment". I would really like to see real butts on all races and genders but they will have rework all the 3D models plus the gear to fit the new body shape. It's clear they do not want to do so. Perhaps in the future they will consider to overhaul the graphics (after dropping the PS3 support I guess) and make use of the higher details 3D models along with the much requested "Higher Res Texture pack" then maybe we can get better 3D models for our characters. I do not think this will happen anytime soon and I'm 100% sure it won't happen before 4.0.
We can only hope for further announcements in the next Fan Festivals where they will tease us with 4.0 but do not hype yourself. We knew DX11 was coming because Yoshi said it a couple of times way before it finally came. We have no hints or even a "promise" that they are working for revised graphics. After 3.0 launched Yoshi said that the graphic quality with further rise in the future but that was all. Whatever he meant anyway. We are pretty far from any graphical update (including butts as they are part of the graphics). Despite we are far from any graphical update we have to keep asking so they will know this particular matter is of our interest.