Yeah, really not fond of the jeans on an athletic outfit. I get the reasoning for not wanting it to be even more work going forward, but that one feels egregious (confirmation Ian always skips leg day when working out).
I guess the thing that bothers me is just that the outfits are being held back creatively when, in the game's design, they are supposed to be the special "stand-out" clothes of the character, something the player had to pursue and spend resources to unlock. If we take Lena's outfits as an example, it is not like the player will get to choose to wear them all the time, they will be reserved for special events, so if they will be a relatively rare sight for the player it will be more dissapointing if they don't look as special as they could.
The core of the issue, as it is currently implemented, is that if the outfits are reserved for special events, it becomes a trade-off between unique CGs for said events and unique-looking clothes for said events, if you have both then the workload to deal with the variations will be very high (I do wonder if Eva keeping the exact same pair of pants for every outfit is because she plans to have h-scenes during one of those events where Ian is shirtless during foreplay, that way Eva doesn't need to do any variations on the CG itself to account for the different outfits).
An alternative method of implementation that could reduce the workload bloating would be to restrict what outfits can be used in a special event (EvaKiss already played with this idea for Lena's first concert, the player couldn't pick the lust or the athletics outfit, only the charisma and wits ones), if the choices of outfits are restricted to purely as an upgrade to Ian's default clothes for different events (i.e, a wits themed event becomes a choice between Ian's brown hoodie and the Wits outfit, can't choose other outfits besides those two), then there wouldn't be too many variations and it could be feasible for EvaKiss to make unique CGs and have the clothes look more different from each other, but it would harm the player's freedom of choice.