Here is my itinerary now:
HND-HKG - JL
HKG-SIN - CX
SIN-MEL - QF
MEL-SYD - QF
SYD-DOH-BCN - QR
BCN-LHR - BA
LHR-HEL - AY
HEL-DFW - AY
DFW-EZE - AA
EZE-GIG - BA
GIG-MIA-LAX - AA
LAX-HND- JL
ignore the previous itneraries. Apart from IST (which i cannot include without keeping it to 4 European segments), i am getting to all my destinations.