More tips-
Find a general approximate broad curve shape for the entire frequency range first, then refine that more specific region by region. Broad changes in distant portions of the spectrum will change the specifics elsewhere. Revisit what you think you got just right. It's probably not just right anymore if you've made changes elsewhere.
In general I think broadly of tonal EQ in terms of thee or four general frequency regions. To get the overall bass, mid and treble regions sounding correct, you may need to smoothly sculpt some stuff out between between those regions.
Lets see, in circumspect, I generally think of a bass region (~<200Hz), upper midrange (say 1kHz to ~6kHz), top end (~>10kHz), and upper bass/lower midrange (~200Hz to 600Hz). I might have something of a broad curve through a few of those areas and work on appropriate transitions between them. I might need to address more narrow categories within those regions, such as in the bass or upper midrange.
Sometimes the mid and top end has mic response resonances and addressing them begins to cross the line from tonal EQ toward more targeted forensic EQ. If hunting to reduce an offending region, find it and pull it down (we can discuss how to find them), then boost a bit on either side of to restore the naturalness of the surrounding spectrum. Play with that push-and-pull aspect of the surrounding frequency range to find a reasonable balance. This works for both boosting and cutting.
Somewhat more 4060 specific, since you use them frequently, although I'm loath to specify anything too specifically-
Try a smooth curve which boosts the upper midrange helping clarity as that seems to improve the presence range of most omnis, drop it down somewhere around 12kHz to cut stridency, then boost the higher treble range to restore the air and brilliance otherwise lost to the depth of the ~12k cut. Likewise at the bottom, for acoustic non-PA amplified material like you frequently record, some boost to the very bottom (even with the flat omnis) along with a slight scoop to the sometimes muddy 200 - 500Hz range can clean up and reinforces the low end. That kind of gentle alternation of boosted and cut areas often works well. When you find a trend like that you like identify it. Then work on smoothing it out and reducing it until it still works audibly, yet is less intrusive. This can be poo-poo'd as little more than making and advanced simile-shaped EQ curve (more of a lopsided 'W') but is something of a general trend.
Be careful cutting that "sometimes muddy" upper bass/lower-mid range, it can be tempting to cut there to let the lower bass bloom and enhance clarity of the stuff above, but much of the power and energy of the music lives there, especially classical music. The complication is that this is also where a lot of room acoustic issues lurk, which is why that region can sometime sound cluttered or muddy. Listen carefully and don't just cut it by rote, which is basically what a Bose system does.
Oh, and don't get overly wedded to the visual feedback of the position of the sliders or the shape of a displayed EQ curve, ears don't see, ears are what mater, do whatever your ears say is good, as confirmed by other, rested and trusted ears.