Thinking about going back to a sailing boat in the 34 to 38 ft size but would like big volume and easy sailing with most of the latest easy bits eg swim platform, single handed sailing, good WC/shower and state room Galley no big deal as thats where I will be - all other reasons should be obvious.

& at a good price so may be 2 to 5 yrs old

Any suggestions for Lake Macquarie sailing ad occassional coastal trip

For single handed sailing you can't beat a self tacking jib. There are not many production boats that offer this but one that should fit the bill is anything from the Hanse range. They have good internal capacity and an easily driven hull with quality construction to match the best of the European imports.
There is a 6 yo 342 (34') asking $169k at http://www.windcraft.com.au/list.php or on the same page a couple of 370e's (37' epoxy hull): a 2008 model for $250k or a 2006 for $198k.
No swim platform but they all have open transoms.
Look at the 350 model too. Its probably the best value if you can find one. They are selling them brand new at the Sydney Boat Show for $199k.
No, I don't have any connections to Hanse other than having owned two - a 400e and a 430e which are both brilliant to sail single handed or with friends.

check the Jennuoe ( spelt wrong sorry) seen the 32 , great boat , comfy, and fast down wind .