"Is there a way to make Kagura go on a solo mission not with Isao?"
Not right now... it will be added in the future but I have to make separate defeat scenes for it
The solo scenes are mostly focused in the town right now
"Is there a way to make Kagura more sensitive to groping by enemies, like making her orgasm in one grope?"
Not exactly in 'one grope' but in 0.2.1 perks now affect that! The more she's subjected to an action the more lust she'll start gaining from it
I'm already working on balance changes for 0.2.2 so it'll be a lot easier to orgasm at higher corruption levels
As for the last two, there will be something similar to sensitivity with debuffs that do pretty much the same thing to make H combat less boring, and I did have something similar in mind with vibrators (and debuffs for the skip turn stuff) but that will have to wait until after 0.3.0 since there's already a lot of things planned for this batch of content x_x