if u considering suprima becoz of the turbo.
forget it.
it is pretty tame and useless.
after the initial fun period after you've adjusted to the speed.
you'll find it is always getting beaten by anything with a 1800cc engine on the highways.
you're better off checking what is common there then only choose.
you don't wanna buy something where the service center is 40km away from where you live.
if you're not willing to commit to high expenses i'd suggest you go with something cheaper to maintain.
although running cost for a honda civic ek standard isn't going to break the bank but one with a b18 heart will.
even if you choose a standard ek there is no guarantee it will be cheap for the first few months untl you sort out all the of gremlins.

Just forget about the Exora, Santa Fe and Rondo.
They're utter crap in the long run.
Exora even with turbo is gutless on the highway especially with 4 adults onboard.
Santa Fe and Rondo may be cheap to buy and seem to have alot of "accessories" but overtime the upkeep won't be worth it especially with Estima and Serena available within budget range.

Estima the most headache part is getting the right spec because basically recon dealers bring in only two spec the 2.4 and 3.5, although the 3.5 v6 would be nice to have on the highways the maintenance bill and roadtax isn't too friendly, but usually it will be the one with the highest spec like power doors x2, power boot, rev cam, etc.

I think the 2.4 would be better for you but beware as some dealers advertise a 3.5 as a 2.4 just to grab the customer to the lot then try and use his salesman skills to close the deal. pitfalls for the 2.4 is the spec, some spec really kosong only 1 power door, some got 2 power door, those got power boot can be considered full spec but hard to find usually it is a 3.5 advertised as 2.4 to lure customers.

As a used car the 3.5 and 2.4 are priced around the same so it really depends on what you want.

The 2.4 has a similar engine to camry and is the more common one on the road so cheaper upkeep. Might be a little sluggish in town with start stop traffic with a full load but on highway it is capable enough.

serena is also a good buy, the hybrid part is like F1 KERS system where it is just used as a boost for pickup, just drive normally and ignore it you can even turn it off......the battery for it is very small coz it is just meant as a boost not a true hybrid....if the hybrid system fails totally it just reverts back to a regular 2.0 no biggie. uses the same 2.0 as the teana/sylphy which is why the electric boost is needed for some oomph. all in all should be pretty cheap to upkeep and cheaper roadtax than estima but imho it is rather ugly.
When people say spacious mpv they're not looking for "c-segment" mpv's like stream/wish/isis/livina/exora.....they're looking for "d-segment" or full size mpv's like estima/grandis/serena/odyssey   
i think you can do better.
my sister got a mitsubishi asx for around AUD7000-8000 i think it was only about a 3-4 year old car.
since you're new to straya lemme share something with you.
locals never buy a car they cannot buy by cash or pay for it within a year or less.
i would say that i30 is on the higher end, unless you really like it then different case.
if u looking for a good deal, that ain't it.

You've got more experience than me there.
I'm in/out since I've family there.
But one thing is true no matter where you go.....service center and volume.
The more common the car the cheaper it would be for stockist/service center to keep parts for it as there is always demand.
The more common a car also means more service centers or outside workshops also make it a point to know the car so they can also profit from regular maintanence of the cars.

This is why like in UK the brand Ford is tops but in Malaysia it is failing.....not enough service centers and parts are bloody expensive.
rich dad logic: everyday also got problem if you got money. 

poor dad logic: buy what you NEED at a price you can AFFORD. so dream car 

salesman dad logic: buy after big season promotion like year end, cny, raya.....coz before these months usually salesman stack up orders to deliver before the festive period so customers can wayang drive back to kampung with new car.....but month after that hangus coz no sales.