I think we got the message from your first post. Repeating it doesn't make your viewpoint any more compelling.
Perhaps you misread the OP's post but they said "I'm booked to go to Melbourne for 8-days." They didn't say they were thinking about it, planning it, thinking of including it in some longer trip or any variation thereof. It's booked (including the hotel). If you have some constructive suggestions as to what the OP might do in Melbourne (in addition to the Old Jail), by all means post that information. However, repeatedly slagging off Melbourne serves no useful purpose whatsoever, particularly when the OP's trip is already booked.
^
Yes, it's a little too late for buyer's remorse in my case. I actually think (thanks to the suggestions here and elsewhere) that we'll do just fine.
Perhaps some people feel their days needs to be jam-packed with activities from dawn to the wee hours of the morning. But for my wife and I, a couple of tours, a bit of walking and shopping, a sampling of good food and wine, and just relaxing in our room works just fine.