Been thinking along the same lines.
With the exception that its only me and the missus and we is getting old and crotchety.
SWMBO has bad knees and cant get up from a low water craft, so I was thunking lightweight tinny with a tiny motor.
More stable, no effort, and a little easier to get in and out of.
I have seen lots of boats on Lake Macquarie, and lots of families.
With the little ones, you might consider an open Canadian, with some outriggers.
Dont take long to assemble, but gives great stability.
Light weight, and easily strapped to the camper.
You can also get a water snake electric motor which takes the effort out of getting around.
The sealed kayaks and their like tend to be a little less stable.
I have pulled a few folks out of the water when they have tipped them and cant get back on.
A bit of a problem a couple of K from the shore.
And with little ones, not good at all.
Whatever you get, please be sure to get the kids "Comfortable" life jackets. Not just cheap ones.
They will enjoy it more, you will worry less and should something go wrong, God forbid, they have a much better chance of survival.
