So far information i can get online - KF
AmBank VI - 2.50/miles (overseas)
MBB MUVI - 1.40/miles (overseas, grocery, MU win EPL match)
MBB 2 Plat - 2.80/miles (weekday)
MBB KF Plat - 2.50/miles
MBB KF Plat - 1.00/miles (SIA, Scoot, KrisShop)
MBB KF Plat - 2.00/miles (Online, overseas)
UOB VI - 1.80/miles (dining - min 1k/month)
UOB VI - 1.13/miles (overseas)
UOB PME - 0.90/miles (overseas)
UOB Lady - 1.50/miles (fashion - with limit)
RHB PVI - 1.00/miles (overseas)
RHB PVI - 2.67/miles (Hotel, Duty free, Dining, Online)
RHB VI - 2.00/miles (overseas)

i'm not sure i missed something, cause only looking at 3.00/miles and below...

Purely airmiles would be to earn with UOB VI and redeem with Zenith at 6,400 UniRinggit for 1,000 KF miles (or Enrich). UniRinggit pools across the cards. This is a feature that is around for years now. Need to check on the first year free annual card fees with Zenith if you are looking at this option? UOB changes T&C often. Zenith card still has some of the World Elite Mastercard benefits although features like Lounge Key was replaced with Plaza Premium lounges after the Citibank acquisition.

Full disclosure I have moved out of spending with UOB as my main cards as customer support is really problematic these days.