We built quite sometime ago and the things I personally wouldn't/would do again are:

Spa bath in the ensuite
900mm shower - would go double
Formal Lounge with dining (we never used the dining)
Double front door - was handy to get furniture in & out of the house but for most of the time we only opened one door
Roman blinds (the gaps let in too much light)
Make sure we got the concrete driveway done and internal curtains/blinds before we moved in

Things we did / changed:
Added more cupboards in the laundry
Added built in cupboards in the study
Got rid of carpet in high traffic areas. So where you would walk into the house and into the kitchen used to be carpet and eventually we put down floating floor boards.
Changed the batten lights to down lights
More outside powerpoints
More outside garden taps