If you are going to spend that sort of money on a jetski (which personally i despise as 80% of people that i have interacted with on the water with jetski's are complete aqua bogans - just tear up the water and drive dangerously close to other water users), why not get a boat?
We have a solid ski/wakeboarding boat for well under those $$$ - its an older model, but is still 270HP, can fit 7 people and puts up a wake the size of more recent boats that cost $70 000 plus. Very quiet inside, and the wake flattens out at faster ski speeds for slalom skiiing.
I just think for a family that a boat is a much much better option as everyone can enjoy it.
This is our boat below - we have about another 5 families that regularly join us for days on the river. Its an american built Ski Nautique and way better quality build than any Aussie boats