If you are only able to find work in Sydney, you don't have to live in Sydney - many people commute from the Central Coast or Wollongong. It is a bit of a trip though. If you are prepared to settle for a unit on the Central Coast rather than a house, they are reasonably priced. Also with your husband now being a wage earner, perhaps you will be able to get a higher mortgage.
The thing about the CC is that their "main" town, Gosford, is not the "social centre" of the CC. The CC is very naturally beautiful but very architecturally uninspiring. However, from a commuter's point of view, one could buy a 2 bedroom apartment with a gorgeous view for under $400,000. It looks like a lot of new places are being built - they are being aimed at commuters.
Real Estate & Property For Sale*in Gosford, NSW 2250 (Page 1) - realestate.com.au
I lived in Gosford for 5 years and I quite liked it.
I note you also said you would like to live in Coff's Harbour but are worried about work. I do agree that in towns like Coff's Harbour and Port Macquarie, you definitely do need to have your work lined up before moving there. I live in PM and was lucky enough to be able to just transfer my "desk" up there (doing exactly the same as I did on the CC) and it is the best move I made. I love it up here and the weather is great - there is a lovely seabreeze all year round. I suspect that those living in CH love it there too. Everyone I know up here seems to love living here - however, a couple of people have had to move to bigger areas because their spouses couldn't find work.