I've mentioned it elsewhere, but I'll drop in here again as well:
As much as Larian have said before that they're adamantly against sliders for character customisation, I do strongly hope that we at least get a few body types to pick from, that being the case. If we can't tweak it directly, then I'd strongly support a minimum of three types; lithe (being slight or slender but still looking fit and healthy enough to adventure), athletic (being the average, likely what we have now) and stocky (being burlier, but again, in a strong, healthy manner suitable for adventure).
More grades could exist within that, but three at minimum, if they won't give us direct tweaking for body type.
In the same category, I'd also very strongly suggest and support height options - again a three minimum, but ideally five, if they won't let us customise directly - one that is the lowest threshold for the race as written ,one average, and one that it the upper end of the race's height potential.
Both of these would also need to be distinct by race; A slender dwarf is not going to be the same slender as a slender elf, a tall elf should still be shorter than a tall human, etc.,
Height might be the more difficult for them, since it will probably play havoc with their intimate character interaction scenes... but I'd still like to hope for it and press for it.
Truthfully if they don't go that route, there will be mods. I know there was already some for different hair colors and using tattoo slot for freckles.