>>537672481
If you want to use her for farming you need a ton of investment since she needs to be able to kill 3 enemies in one wave often.
Meaning her Buster Card has to one shot, then her NP has to one shot, then her last Buster and Extra have to be enough for the 3rd enemy. Pic related for a random ass Bleached Earth example.
For just CQs and shit she is fine at NP1, though obviously more is always better.