i hear what you are saying and it might be quite nice to make the GEQ behave like your GEQ of choice. Whant a Mesa 5 band no problem. What about an MXR 10 band........ etc
however, you have hi the nail n the head with your own explanation. In reality you are using the EQ to “fix” a problem area either to enhance or reduce certain frequencies. How many times are there actually 5 frequency bands that are all problematic?if that is the case there is probably a better profile to start from. It should be possible to fix an already good profile with one or two bands. Or to run two Studio EQ in series (although this obviously ties up a slot that could be used elsewhere).
i can remember the actual frequency centres for the main Kemper tone stack but I wouldn’t be surprised if they already fall in between the bands of the GEQ.