I've been playing the Autoharp for more than 40 years. I have about 10 of them right now. Each one has different tunings and chord bar sets. Yes, they go out of tune a lot, and each one has 36 strings (except for thoser little ones and an off screen Omnichord).
I do a lot of experimenting with tuning the strings and making chords. You can read about those experiments here. But at some point, you run up against physical constraints related to the number of chords, the number of strings, and how to tune them.
The Suzuki Omnichord (that white plastic thing in the front) is a kind of a hardware solution to some of those problems. It has 36 Chord Buttons, a lot more than can fit comfortably on an Autoharp, and can actually play about 84 chords. It's now called the Q-Chord and has MIDI output. PolyHarp's internal synthesizer actually sounds a lot like the Omnichord's.
PolyHarp can be thought of as an update to my old Commodore Amiga program LYR, which was a chorded zither simulator I wrote in the late 80s.
It played MIDI synthesizers and had some pretty bizarre chords and features, including a strum sequencer. But LYR never got to a stage where it was user configureable.
It nevertheless was a pretty impressive MIDI controller. It was especially good at providing an easy way to control MIDI velocity, which sounded especially good on the Yamaha DX7.
You can read about LYR and other old Amiga software of mine using this link.