You're not wrong, but I'd counter with variety is the spice of life, and people like the new and novel. If almost every woman in your two games ends up with the same style for their 'slut' modes, it looks like you're in a rut creatively. And it's not that EK can't do it, the boutique classy dress is a great counter-example; it just gives off path of least resistance vibes when you don't try and personalise it for the characters, to reflect them more individually. But that's just one opinion.
Counter counter point. I would argue that the "slutty" outfits are personalized.
Slutty Lena and Ivy are cut from a similar cloth. They have a long outstanding history with each other and, on the slut route, have a very similar past that would largely inform their dress. If Lena takes StalkFap seriously, similar to Ivy, then it's probably their fans that are largely informing their dress.
Holly hasn't achieved full slut status yet, as far as her wardrobe, but it has been far more conservative and maintained a "girlier" appearance that the red and blacks of Lena, or the cool neutrals of Ivy. A lot more pastel in her palette. Holly's slutty bikini is also quite a bit different in both cut and color combination of either Lena's or Emma's.
Cindy doesn't have a true "slutty" appearance, but her wardrobe has also evolved over the course of the game, fitting her relationship appropriately depending on which of Ian / Axel / Wade holds her attention.
Allison's slutty outfit is again much different from any of the other girls. Her top is more of a boob window than a bra with frills like Lena's or Ivy's. Her shorts also cover more of her legs, never quite getting to booty shorts length. Her dress is very different than either Lena, Ivy, or even Cherry's. Not that Cherry's dress is intended to be slutty or eye catching.
Minerva's slutty outfit is so damn subtle I doubt many even noticed it. She just leaves the top of her blouse a little more open, and her underwear changes to a thong.
So that leaves Emma. Who as I've mentioned before, does not have a sense of style. It's been a part of her character since the beginning. So Ian tells her to dress "hot?" Well the hottest she's dressed so far was her time at Blaze, and her only other frame of reference is seeing a hot / slutty Lena. So her current outfit is in line with those two reference points.
It probably won't happen, but I think the key here again, is EK saying we can let Emma know she has no sense of style. Which both Ian and Lena can comment on already to varying degrees. A posh Lena can help Emma find a nice mix of stylish and slutty, similar to her charisma outfit. Ian can say he loves or dislikes the whore look and Emma can either go back to her normal "hot" outfit, or can embrace the whore look. We don't know yet, but EK hinted at there being an alternate outfit to what was shown.
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