I just started playing today. I'm up to 3-1 now and this is what my team is looking like. I'm making the most with what I got.

Tsurugi is a tank, but her healing-on-kill is unreliable
Saki and Maki are good single target
Hanako good AoE healing over time
Kotama has a good AoE attack buff that I keep up
Chise is honestly the MVP, her AoE fire DOT skill melts groups of enemies, she's really powerful