Interesting thing though, in some pretty extensive testing I've found that two versions of the same plugin[1] get very different opinions on sound quality depending on whether or not I use the skeupmorphic interface or a "flat" one drawn with normal toolkit graphics (I don't have a screenshot but think in terms of Ableton's vector graphics knobs).

Almost everyone seems to think the one with "real-looking" knobs and front panel "sounds better", "sounds more like the real synth", "has better filters" and so on than the flat design one, even though the DSP code and control ranges are identical between the two.

If you don't want to use knobs, what would you use instead?

[1] https://gjcp.net/plugins/peacock/