I started with vivacious and maybe haley and amelia, but I had no problems with the ghosts. I did everything pretty much the first week so my gear wasn't that amazing either. The most problem I had was when my tank was Velvet and she came to a world where she was countered. She's already a bit squishier since she does damage and has an invincibility skill, but against the personality she's weak to she just explodes in 1 second.