ReaFIR set to compressor mode seems to really deal with harsh resonances without fully EQing things.
I.e. a EQ will just squash all the frequencies down evenly in thar range, whereas this style of compressor seems to dynamically reduce harsh resonances, making the sound more pleasing and able to be louder overall.
Basically its like compression applied with an EQ curve, and likewise just targets spikes in frequencies in those particular ranges, allowing you to keep more sound and clarity, but while drastically reducing harshness.