I wonder if the OP is referring to the DETAIL of the instruments? For example, a guitar sound on HSSE does not, of course, sound “good” to me because the level of detail is not there. I am referring to the number of different articulations, tones, etc. In other words, they don’t sound REAL. Like a drum roll that sounds like a “machine gun” effect because the instrument is not using several different samples in random order, etc.
If that is what the OP is referring to then I would say it is just a result of HSSE being an entry level instrument that covers a broad spectrum of instruments and doesn’t focus on one with extra detail.
If you want a high level of detail on, say, a guitar, bass, or strings, it may be necessary to buy a Kontakt instrument that focuses on a high level of detail.
If we are just talking about the SONIC quality of HSSE (i.e. the sound engine), personally, I think it sounds pretty good.
J.L.