My soundfonts probably sound natural because I play just about everything in myself, on my MIDI keyboard. MIDI data plays a big part in how natural a soundfont can sound. Like, if every note is exactly the same velocity, and absolutely perfectly timed, it sounds like a robot's playing the music. But if you record the MIDI information yourself, there can be nuances, variations ... hell, mistakes. And that's what makes it sound more natural.
Like those piano chords. They're three note chords, but not all 3 notes sound off at EXACTLY the same time, they're just ever so slightly off, like just the tiniest fraction of a beat, just like it is when a human being plays them (because I am a human being, and I played them). But, uh, yeah that's something to consider when you want your music to sound natural. You don't really notice that it's just ever so slightly off, but it IS noticeable if it's perfect. And that's not always a good thing.
I do edit and tweak the MIDI data after I record, though, but only if my timing was way off, or that one note was way too loud/soft. But never aim for perfection with MIDI data. You can tweak it yourself to allow for slight changes in how heavy each note it hit, or making each note just so slightly off beat (without REALLY being noticeable, it's all about subtlety), but if you use Logic there is an algorithm you can just "apply" to the data. It's called "humanize." It's a bit much by default, and you need to tweak the settings and dial it back a bit for it to be effective, but ... yeah, that's pretty much it, I think.
I do hear what you're saying about the harshness of that instrument (it's a koto). I wanted something weird and enthnic-y, but the acoustic Koto was weak, and I couldn't find a good instrument to layer it with, so I thought "shit, put a guitar amp on it." And yeah, haha, I kept it that way.
I'll check out your track when I get home from work.
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