For Ringo and Seiran, I was thinking that they would be Heart types, but that was just operating off the fact that Reisen, another moon rabbit, was also a Heart type.
Doremy is definitely a tricky one to figure out, but I really liked Drewko's idea.
Sagume and Hecatia should both be Faith types given the fact that they're both Goddesses. I was thinking Faith/Flying for Sagume and (initially) pure Faith for Hecatia. She would gain a secondary typing through her evolutions. Through leveling, she would become Faith/Dark with her Moon form. Through shards, you could get her Earth form (Faith/Earth) or her Dream World form (Faith/Heart?).
While Dark/Nature sounds good for Clownpiece, I personally prefer Fire/Nature.
I think Junko should either be pure Dark, pure Ghost, or Dark/Ghost.