Fennekin is absolutely badass. Definitely my favourite so far. Froakie probably the least so, which isn't to say he's bad.
I'm not one to predict secondary types so much (because I'm almost always wrong), but my initial thoughts are that Froakie will probably stay the same, or may even develop a water/grass combo. As for Fennekin and his/her "psychic" attack, it is worth pointing out that I think he/she was fighting a Ralts at that moment. Could just be a reversal/mirror coat move? Doesn't immediately suggest psychic.
I dont think that a starter would get a second typing that is the same as one of the other starters. Froakie looks like it can end up being pure Water, Water/Fighting (Journey to the west reference, like Infernape and Emboar) or Water/Ice.
I still support the idea that Fennekin (I will never get tired of that name) will end up as Fire/Psychic.