Several things here. If your 175 is granted you can go alone before your family. The grant letter/email wil give a date by which you must all enter Australia. YOu can go first, but the family cant enter before you, they can enter with you, or after you remembering whatever date you are given. It very hard to have that date extended, so make sure you get in in time. But thats not a problem for you based on what you say.
Im not sure if you already have the 175 visa?