The Moonlight track is alright for a XC ride, but nothing spectacular. Yes I have, cycled up Coronet Peak yesterday and rode the trails (see Trailforks) down to Skippers Canyon. A shitload of climbing if you start from QT but definately worth it!!
That's a sh*tload of climbing alright! You should try riding Moke lake to Lake Dispute, if you haven't already, mostly XC but at the end it connects to some sweet single track via Phoenix. You'll need to go across Glenorcy Rd though!