She has a RoF buff skill, which Arcus was saying won't be as desirable for Isomer ranked. I should've said "Who even has RoF tiles, and a useful buff skill other than RoF?" Stechkin, 5-7, and Calico all have good tiles and useful RoF buffing skills, and I have all of them.
I... don't remotely understand why RoF wouldn't be valuable with the right teams, especially in regards to Calico who also carries a pretty large accuracy tile on maps where you're fighting 35-40 EVA unarmored enemies alongside 10-15 EVA armored enemies, at night, with
RFs. As long as you aren't going all in on it, you can still mix in enough FP/critical damage multipliers to clean house.
Example: M950A (Calico)+Px4+Grizzly will provide 110% accuracy from tiles, or you could sub Grizzly for SAA for another 50%. Then you can put in two RFs; one with a sure-hit, high damage skill (read:Grape or M200) to kill gundams, and the other with any bog-standard self-buff (though Type 4, T5000 and SRS will excel here for varying reasons).
The main thing to keep in mind is what tiles are less necesssary based on the RFs you put in. M200 doesn't care about RoF, while Type 4 benefits less from crit damage since her piercing shots don't crit.
Fairies are a pretty important balancing factor as well, for the same reason; if your team ends up lacking accuracy relative to other things because the HGs that work with them don't provide that, a fairy that -does- will serve them well. Candidates for accuracy-boosting fairies that also provide other useful stats and skills are Illumination (38% crit damage/90% accuracy), Warrior Fairy (25% FP+80% accuracy as well as skill for +20% FP/+10% ROF), Rescue Fairy (32%FP+80% accuracy), or Taunt Fairy* (18% FP+25% crit damage+58% accuracy).
*Don't use her skill here, for the love of god. The reason being is that gundams will spawn -much- further back than they did in CT, giving them time to walk up and missile spam your echelon if they stop for whatever reason, including if they stop at the Taunt dummy.