Hey mate, hope you're fine and it seems you're kinda new to mixing and/or production in general, if that's the case I wish you luck in your musical journey

That said, I don't think there's a standard of what is aggresive or gentle in terms of numbers, it's all about how it sounds actually. Does your EQ move changed the source material a lot? No. Than it's subtle, otherwise it's a more aggressive move, and don't get the words so roghly, sometimes drastic moves are exactly what the sound needs.

My advise is to forget about the numbers, as long it sound good it's good, and that's the objective. It's true for any processor like EQ, compressors, saturators, reverb, etc... There's no right or wrong, the numbers are just for technicalities, any source material will sound different and there's no magic number when it comes to audio processing, just do whatever your sound ask for.