(F2P Inf Main) Charles Martel vs Aetheflaed for Sun Tzu

So, this very evening i unlocked both of these guys, within minutes of each other but, is charles better for Kvk1 to pair with sun tzu (lvl 40 atm) or should i no matter what focus on Aethelflaed bcuz of AoE? From what i gather CM HP/DEF and Aethel Open Field DMG

Up to not too long ago i woulda focused on Aethel but CM's shield and extra tankiness make me wonder if shes really THAT good just due to AoE

If Charles is better, should i invest sculptures?

Also regardless, of which is better please tell me on what talent tree should i focus

Also this is a 12 day old server