In term of RG I'll say Lilac Squirrel, Jack-in-the-pulpit, Pincushion, Persian Speedwell, Crinum and above all Tritoma. But Tritoma is Event girl and her reprint is already over. There is others nice girls but thoses are the most interesting I guess.

I think Heart Tree was really nice when she came out but now, she joined the others as okay-debuff-girl-but-not-top-tier. Still usable but won't do miracles. She lacks way too much tools. I think honeysuckle easter is a better miss debuff (but a really poor support). Jack-in-the-pulpit might works better with Cotton for the Crit side.
But Maple with intercept?