Pretty often I want to suppress cymbol sounds and other raspy harsh stuff.
Is 30 band equalizer the best choice? Usually around 4k, 5k, 6k. Is there some
tricky better way?
It depends a bit on the effect you need. The 30 band graphic is good if you want a gentle cut over a range of frequencies. However, if you can identify one or two seriously bad single frequencies, then I might try the parametric EQ, find the ideal centre frequency, adjust the width (Q) to the least you need and cut as required.
The 30 band graphic is like a butterknife--great for broad brush strokes stuff. The parametril is more like a surgical scalpel.