I am glad this was mentioned. I just put a request in for this very thing yesterday. My Novation SL49MKII from 11 years ago, allowed this right out of the box and I immediately tried to set the Keystep Pro to do the same thing, as soon as I turned it on, as it is how I play my stuff in and was quite annoyed when I saw curves listed in the settings, but no option to set a value. My Novation allowed from 0-127, the full arrange and it would always play at that, until I changed it again.
This is exactly what needs to be in the Keystep Pro. Not just curves, but allowing of a single value from 0-127, to fulfill anyone and everyone's needs. No one likes being stuck to a predetermined value by the manufacturer, that may not suit their playing style.