for anyone interested, I'll post my settings here. i have the 2023 carbon edition cx5 with bose. for what it's worth, I'm a part time audio engineer and review audio equipment (mostly headphones) on YouTube. just to say I'm familiar with a lot of sound science and have heard many playback systems in my life.
i have a fondness for studio quality sound, meaning the sound of a well designed acoustic studio space with flat measuring studio monitors. you can easily get into debates on what that means and objective vs. subjective sound preference. but my point is just to say I'm not just voicing a completely uneducated opinion. I'm not claiming my settings are the best or anything, but just that i feel they most closely approximate what i personally perceive to be a neutral sound in my experience.
I'll start by saying the bose system does some things very well and some not as well. and that no matter what you do it doesn't sound completely perfect, but it is fairly capable for a car system. in fact, it does more right than most imo when tweaked.
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I'll list each setting and explain my reasoning.
first, i start with all enhancements turned off.
audio pilot is just volume auto adjustment based on road noise. that's a personal thing. not for me. choose what you prefer.
centerpoint off. this adds a surround sound style quality which can be cool. any setting beyond 1 ruins the stereo image imo. but even turned on 1 the sound becomes wider but much less distinct. it also changes the subwoofer relationship to the speakers. so off for me.
fader and balance default 0. these can be adjusted to taste, but with my settings, 0 will give the most neutral frequency response.
listening position set to driver... screw all the passengers:

but really, this gives the sound a more direct and precise imaging akin to speakers in a room. and it is not a drastic difference to passengers.
here's the biggie. stereo mode set to linear. this is big because the bose setting is essentially an eq that gives the sound more bass punch and treble sharpness. it does this at the cost of mid frequency accuracy and gives the sound a"V" shape eq tonality.
it may seem counter intuitive but with linear stereo mode it sounds much thinner and weaker. however, you need to set bass and treble to +7. this brings back bass and treble presence while retaining more mid range than the bose stereo setting. you can tweak up or down a point to taste, and passengers will affect the perceived response, but this sounds good to me.
make sure to disable any eq or enhancements on your source player. once you get used to this it can be further improved with eq in an app like poweramp by increasing lowest sub bass to taste.
again this is to mimick a neutral speaker response as much as possible. if you like the enhancements that's cool. I'm just going for response and imaging accuracy.
with these settings, what i find the bose system does well is overrall smoothness of the response. there are no major peaks or dips in the response. nothing objectionable. it is very resolving and smooth.
what it doesn't do amazingly well is bass impact. it's very smooth and clean bass, but to get sub bass punch and fulness you need to ruin the mid bass accuracy. so i opt for these settings. granted, to me they still sound great and bass has nice sub bass extension and hits well enough. but there's just always a certain oddness to the bass or mid bass. almost an out of phase quality. but these settings minimize the issue the most.
so that's my recommendation. give it a try and see what you think. i haven't spent a lot of time yet so i may tweak things slightly, but this is what i have settled on initially.