With the Peterson StroboPlus HD, I'm able to define my own sweetened tuning that I've customized for EVERY pitch available on my 12-string extended E9 pedal steel guitar. Pedal steel uses pedal and knee levers to change the pitches of some of the strings, and those changes are tunable. So each open string has a user-defined value, and each tunable change also has a user-defined value.
Ultimately, it would be ideal to be able to take every pitch (C-1 to G-9) and define a custom offset. That would be saved as a user sweetener, and then it could be shifted up or down for use with a capo. I think that would cover just about every possibility, for just about any instrument with strings and a pickup?