The obsessing over Zarah is all from this weird retentive need to have every single female in an adult game look 25-38 (but really 22) with smooth curves and no real facial differentiation. Any deviation from that trope brings a litany of cries and insults.
Cheeky has done a nice job trying to keep his story close to "realistic" and I greatly appreciate his choice to try to keep some of his models that way, too. While Jenna might have been a bit too pale, I hope she doesn't turn into another carbon-copy bronze girl. Her character was written as a shy, stay-in girl...a lack of tan is the right call.
Similarly, Zarah is portrayed as a mature, experienced (and somewhat hypersexual) woman. If she shows a bit more character in her appearance, that's again a grounding factor in keeping the game "real". And, for those trope peeps, since it's only necessary to be nice to her, you can avoid the "horrible" act of having sex with her (as if any of those players would turn down a sexed-up mature in real life...especially with those curves!).