Sunny does incredible damage on her own- Its quite easy to get 2-3 medals per match, each worth 3k damage to the monster (meaning youll have done 1-2999 on top of this as well)
To go with this, she also augments/increases the teams overall damage by rapidly repositioning her team mates such as the assault, allowing them to better maintain appropriate distance, both in the dome and on the chase- Which is another strong point of hers, she allows highly aggressive maneuvers on the chase.
She allows better trapper positioning to secure stronger other wise unobtainable domes in a plethora of situations
Her boost works as a form of soft CC when you factor in how it puts a demand on monster traversals
And many, MANY other things
ALL while having some of the most powerful defensive capability for both her team, and herself.