Obako don't looks that bad. She just lacks a bit of survivability. Her skill based buff is carried over the whole mission. Good for multiple battles. With good support, she can do the job.
R-medals girls are usually meh-tier. Obako may be one of the best with Pavonia.
For support, it depends on what you call good support. There is a lot of usable support girls but if you want Hinoki level, it's almost non-existant.

All the easter girls are very good this year. And their combo makes one of the best intercept team possible. Too bad I don't have enough gems after Sigilaria.