>>366813264
nah, if the avatar is under 70k polys to begin with, the rest is fixable even if you're shit at topology or shit at remaking shape keys (like I am, on both counts).
retopologizing the face also isn't always necessary. i had an avatar that was only high poly because of the outfit (some MMD 9S outfit, looks great but is absurdly high poly). painstakingly dissolving about half of all horizontal and half of all vertical edge loops got it down far enough.