Agreed with above. I recently did almost the exact routing of your option 2 - LHR-HKG (BA) HKG-MEL(CX) - best of both worlds.

But gotta say I got less sleep HKG-MEL than LHR-HKG due to WB. BA seat is better, CX service and IFE is better.

MB Spa is great. Concorde Room is good but would not be a decider for me personally.