Being New South Wales born yet living in Queensland more than half my life now, I am not overly knowledgeable about VIC but have had quite a few trips down there now, our most recent VIC holiday last September we toured ourselves through the Mornington Peninsular (which we loved, but can understand why you wouldn't be too excited about it being that you're from there, same reaosn we're not gaga over the Gold Coast anymore I guess!) and then went out along the Great Ocean Road which was absolutely stunning! We stayed in Lorne & Apollo Bay and both were gorgeous cosy family friendly towns which I think would be perfect for a beach getaway! Lorne is alot bigger than Apollo Bay and probably has alot more to do but both were beautiful places, I think Lorne was about 2 hours from Melb and Apollo Bay about 3.5 hours.. Don't quote me on those exactly but I think that was roughly about it from memory!

I hope a VIC local can give you more info and choice being that my experience is kind of limited. Such a beautiful part of our country though! I hope you have an amazing time wherever you choose!