Here's a useful generalised curve I worked out years ago in desmos. You can easily implement this in core. It's useful for tuning while developing. Best to then convert to fixed settings for efficiency. Also fixed settings are much simpler to implement with Anti-aliasing.
It is possible to implement this adjustable curve with ILO, but I wouldn't recommend it except as an interesting challenge/excercise ;)
It's very easy to modify this with asymetrical settings too. Piecewise FTW
https://www.desmos.com/calculator/b0kn7a8u0g
