Depends on what cards you have and availability.
Avios, I agree, appears to be the best bet.
With Citi Prestige you can transfer at 4:1 to Avios partners (BA and QR).
(CP to Asia Miles is option at 15K miles each way, economy per pax + ~$50 taxes)
Else you’ll have to go the Atlas/Magnus/Reserve/Infinia routes at respective rates to Avios.
or
Accor to Iberia > Avios.
If you don’t have a ton of points or availability is an issue, you can consider paying cash (traveledge or smartbuy) to get ton-ish points, if rates work for you.
S&M