So, here's the thing.
You didn't mention how much gear you need to haul.
If you're a minimalist, you know, a jar of Peanut butter and a sack of bread does your family for 3 days, then yes, a paddle boat is one way to go.
If you're like most families, you'll need a HUGE tent, air mattresses, a shower enclosure, lanterns, stoves, music, a generator, and so on. In this case, no, a paddle rig would probably not work.
Plus, you gotta consider your skills when it hits the fan; will you be OK repairing your only ride if someone somehow pokes a hole in it? If you have a major flip, that you know, leaves you standing on shore wondering; What? will you be prepared to hike out?
On the whole, I would want two or more boats on anything but a Gore or Glenwood run, just to be, you know, safe. And besides, you got a couple of boats, someone gets out of line, you can chuck them on the Mini Max or the IK and tell em to chill. Plus, you can haul more stuff, to you know, please the group with some comforts when it starts snowing on your June Deso trip.
Or, they can tell you to chill and make you row upstream. Or sumpin.