Good ideas, I'm not sure about the gag, but her own little panties would work well, and be appropriate since her punishment is for flashing them. Yet, a babies pacifier would be a nice addition as it would humiliate her so much -- although Kate dresses innocent, she likes to have a bit of a sexy edge (hence flashing her panties). To treat her like a naughty little girl and shove a dummy in her mouth would be amusing.
Yes! I'm particularly keen on tit torture too..
Slapping her fresh young breasts around for a while to make them all red, and then clamping her nipples would indeed be fun. You could attach chains to the clamps and put a few weights on the ends, making sure they were hanging nicely. With all these things I'm sure that by the end of it Kate will be willing to swallow her pride.. and anything else you might want her to swallow !
What sort of girl are you correcting her into being? Just obedient and polite to her guardian, or more than that?

Prey4me, I like your ideas, wow, it'd be damn hard to suck someone off while hanging upsidedown! But it would be a nice treatment and a challenge for her if she's a bit arrogant and thinks she's good at everything.
Personally I like the idea of turning her into a proper young lady.. willing to do anything for her guardian, yum yum!