Rank Up suggestion(for act 6.1 )

dharkconspires

I can either rank up "3 r4 5*s" or "1 5* and 6* r2". I especially am struggling with my current team to become cavalier so who should I rank up?. I also have 5* human torch and bwdo as r1's too which might take time to rank up. or a 6* mr fanstasic