There is an area in between traditional acoustic instruments and the synthesizer that is of special interest. Although my exposure to electronic music now consists entirely of YouTube demonstration videos (I don't ever list to synthesizer music on the stereo, but only sacred and classical) so that I'm anything but an expert in synthesizer music, as far as I know, this sonic area is fairly unexplored and generally not of interest to folks. I can only describe it a being 100% synthesizer, and yet, strongly reminiscent of acoustic instruments. It also effects the way I categorize sound programs on my instruments. For example, I'll typically have groups of ten programs each named according to a pre-existing acoustic instrument - reed, flute, piano - but the various programs in each group will not actually attempt to imitate the reeds, flute, or piano. So, the term "reeds" is used only as a general tonal description, meaning only, "sort of reedy." The programs will be named "Reed 1," Reed 2" etc.. My point is, the synthesizer has the wonderful potential to make sweetly natural and musical tones that sound familiar because they do fit into familiar sonic categories, and yet, are entirely new sounds. So, what is a Reed 3? It's a synthesizer program that sounds a bit like an oboe, but definitely is not an oboe, and yet, can be used like an oboe because it sounds similar and quite natural. What is a PWM Piano? It's a synthesizer program that sounds a bit like a piano and a bit like a harpsichord, but is definitely neither, and yet, can be used very naturally like both. The key is in the many natural sounding nuances of the patch, avoiding anything overtly electronic sounding, and in designing each patch to exactly suit the piece of music you're making.
One of the most popular nuances these days seems to be Slop. Personally, I find it to be anything but natural sounding, and never use it; it sounds too forced to me. The important nuances I use are: both subtle and dramatic dynamic changes, smooth delayed vibrato, faint phasing of various types, an opening of the filter as one ascends the keyboard, a very modest use of resonance except when in 2-pole filter mode, a constant stereo field but with no panning back and forth, and - most unpopular of all - avoiding anything course or bizarre. With these nuances used as a sort of guide ("rules"), the unnatural and unmusical (yes, that's in my judgment) are avoided, and a whole world of sound that seems often missed by the synthesist awaits to be discovered - sounds that are so very oboe-like, violin-like, flute-like, and so on.