I've been really lucky I managed to reroll Lyn and Jakob and then I pulled Minerva, Cordelia and Hector in the same pull, I have 11 altogether.
Sorry about your bad luck
My team is not good at all I have Eirika+1, Nowi , Hector and Takumi.
I lose a lot my last run I came up against a Takumi Lucina and Hector all +10 I can't compete
I upgraded Nowi to 5* she's been amazing for me.
I was lucky to pull a 5* Cordelia she's great too but Azura takes that spot in my team she's just too good to take out.
Lyn
Jacob
Takumi
Azura
Minerva
Hector
Cordelia
Cain
Eirika
Ephraim
I've been so lucky I've managed to get 3 top tier characters who destroy in arena.
I'm hoping I get a 5 star magic user or dragon next.