Agreed.
I booked a MEL-SYD hop for next year to catch up with a friend for the footy. The SYD-MEL leg is in J as it's decent. There was oodles of availability too.
Internationally though, VA is pretty dire so conversion to SQ is definitely an attractive option.
SQ - reasonable for PE, but J gets picked over by the time 330 days rolls around meaning it's luck of the draw what else shows up. Even then, carrier charges are crazy high compared to SQ itself.
UA - holds back long haul J redemptions for credit card partners these days making redemption difficult.
AC - no rhyme or reason as to when J comes out particularly to/from Australia.
QR - okay, but I suspect this is down to the current troubles, and many (like me) have a strong preference not to fly through the Middle East for the foreseeable future.
NH - picked over by the time 330 days rolls around.
HX - okay, but managing bookings is a chore.
VS - a total coughshoot whether the call centre can even book an award (as I discovered trying to book one in whY).
SAA, Hainan, Capital and Tianjin are all fairly niche.
I suspect that with QR in OW, VA won't end up in Star Alliance though.