So what's your definition of monster girl? Do the elves, giants, and Rosy count for that? They don't for most people.
Not counting Qetesh the game has 32 girls currently, 33 when 3.6x drops. Rounding off:
- 9 human is 28% of 32, 27% of 33. Alice, Beth, Gwynneth, Jenny, Julia, Mia, Oksana, Victoria, Ziva.
- 8 effectively human is 25/24%. 4 elves (Caleah, Erevi, Liandra, Luthien), 3 giants (Birgitte, Frida, Hilde), 1 Halfing (Rosy).
- 15 (soon 16) clearly monster girls ranging from goblins to Naamah to Venomina. 47/48%
Human plus effectively human is 53%, 52% once 3.6x is live.
If what you're wanting is human-focused content dealing with Weirdwood and/or Greyport, or more for the Main questline, those are pretty much guaranteed after 3.6x is done.