Having just returned from an extended camp trip w/ 4 AIs and 1 TI, I would strongly suggest you do a trial run yourself, maybe w/ your wife or someone else.
Do the trip you are planning. You will get a pretty good idea about how much your boat leaks, and what precautions you need for gear. Personally, I load all gear I want to keep dry in the bow. Gear that is water impervious(stakes, pump, pee bottle, bottled water, Gatorade bottles, etc), I pack in the stern--remember, when you pull up on a beach, your stern is low and will collect all the water in the boat.
If you look at my thread on AI camping http://www.hobiecat.com/forums/viewtopic.php?f=70&t=7276&start=0
you will see that I have complained & made suggestions extensively about water leakage into the AI. My 2007 AI, now leaks about 1-2 qts of water (from the rear) on a very rough day (it does not leak if I simply am doing a day sail or running fully-loaded downwind.) My wife's 2009 AI leaks very little on the same days.
My tent is in a water-repellent, compression bag and simply jammed in the bow. It is 2" off the bottom. I bag all my clothes in a pointy Sealine bag, expel the air, and jam it as far forward as possible into the bow.
This may surprise people (they will probably say I'm nuts), I do not dry bag my sleeping bag. My bag is a Mountain Hardware Ultralamina (http://www.rei.com/product/747877
) It is synthetic and packs very small (6.5 x12 inches) into a water-repellent stuff sack—I jam this high in the bow along w/ my clothing bag—it is about 5” off the bottom. Kitchen gear is in a dry bag w/ the opening 3” off the floor—same w/ food bags. Tent poles are always in a dry bag—you can ruin aluminum tent poles by allowing them to get in contact w/ salt water. I have numerous small dry bags, and I try to keep their openings 2-4" off the bottom.
On the trip mentioned above, the TI leaked significantly, as did one of the AIs. You have to tighten every screw, seal any opening which may leak w/ goop, and pay close attention to keeping the TnS hatches clean and the ring lubricated w/ silicone grease (most spray lubricants, like WD-40, will ruin the O-ring.)
Regarding the TI and leakage, since it has more holes through the hull than the AI, it has more to maintain. I don’t see why it should be any more prone to leakage than the AI, if everything is maintained. The rear hatch is slanted so water does not sit on top and leak in thru a poor seal. Still, there is nothing like doing a practice run, BEFORE you take your wife & daughter out. A bad experience will likely end their interest in doing any further TI camping.