When you say rejected, it is really rejected or it is just in a "cannot be finalized" status where more information is required?

I guess with the Australian immigration, really have to give all possible information (esp those financial related) that you have to prove that you will be coming back. Makes life easier for them and for yourself as well

Some that I can think of:
Employment letter, leave application letter
Recent payslips (3 months)
Bank statement (with sufficient funds)
EPF Statement (plus any other significant investment statement)
LHDN EA form
Housing loan / geran with your name on it
Children school enrollment letter

If you're self employed, company SSM registration, form 49, company bank statement are useful as well

Every bits of information helps for them to determine if you're a genuine tourist