Just my humble opinion on the Canton in my Kodiaq. It has a couple of quirks that can be a PITA sometimes but otherwise, in comparison to the standard system it's night and day.
I adjust the very simple EQ depending on what I listen to but to get the best of the system you really need to be turning the bass way down and putting the Subwoofer volume on around 6/7. It also makes a huge difference changing the "Focus" not the balance/fader to "Front" instead of "All" and turn all bluetooth/loudness etc to off. This makes the system come alive and being that you won't be listening to music loud with kids in the last row, no one else will be missing out anyway.
The connection method makes a difference too. I'm lucky enough to have a separate work and personal mobile phone, one android the other iPhone. Both phones by bluetooth are acceptable but the iPhone quality is marginally better although doesn't go as loud.
If you really want it sounding it's best the source needs to be good. The best so far is either Amazon Music HD or Tidal through Android Auto, because then the in car DSP is decoding the sound and not your mobile device. Spotify works ok, but at almost full volume can get a little sharp or harsh at the top of the range. No such issues using Tidal.
Just my two pennies. Sounds is a very subjective topic but if I had the option again I would add Canton in a heartbeat (it's the ONLY option I picked other than adaptive cruise). Saves messing with paying silly money to have someone take your car apart to fit a professional system, especially if it's on lease or PCP....