Karon is not so much an actual tsundere, she's more towards the yan/sado side, like Rin is. Right now, she's has no time for love. Career comes first. Her actions have been leaning towards denial not for the same reasons as the others, that's why I don't consider her tsundere. After all, if given the chance, she'd be rather open. In fact, I'm still tossing up whether the two of them are already going out but put on hold because of ISA and Gladiator matters.
Not sure about the last part, Fuuko certainly isn't kicking Max any time soon.