Two mostly cosmetic suggestions:
1) Bunny Ears in a typical bunny girl/boy style as a cosmetic character creation option ... but would be surprised if this has not been suggested before and/or already present however.
2) Additional cosmetic character reactions and interactions.
This one is a little more complex but might be an interesting addition:
2a) Hovering over or clicking on a location with the mouse cursor could change the character expression depending on arousal level [condition 1] and if the area is covered by clothing [condition 2] if not in an event [condition 3].
2b) Clicking on interactive elements [condition 1] of the player character [condition 2] may apply a visual change to that location if not in an event [condition 3].
Example 1 : Hovering or clicking over the characters covered chest with 50% or less arousal and the characters expression may change to an annoyed one which would automatically disappear after when something changes in game, like entering combat and/or moving.
Example 2: Using the rabbit ears suggestion mentioned above, clicking on them could cycle through a series of visual options - both up (option 1 ), left down right up (option 2), left up right down (option 2), both down (option 3)