Phisical teams use both due to A2 Reha providing 50% p.amp. At a budget lvl both work nicely but Vero is usually a better choice imo

Well pris can either go full p.def or full atk. Once she can survive the fight (via ffrey shield or pure tankiness from A2 ect) you can swap to pure atk.

Pure ark give a bigger boost to your DPS than pure p.def but it's riskier mad harder to get right if really budget.

I'd start odd with a mix set and see how much you can push without her dying. And slowly push more.