Just my opinion, but I think Steinberg needs to encourage third party development for their VST instruments (or release more expansions themselves). I saw that there are some “Synthesizer packs” for Prologue available. About six months ago, I was considering buying HALion Sonic (or possibly HALion 4) but the reason I decided not to was because I have not seen much activity in terms of expansion packs for them yet. If you look at Kontakt or Reaktor, there is a large selection of stuff available. I REALLY like that HALion Sonic is VST 3 and has Note Expression, etc., but I couldn’t help feeling like there wouldn’t be many new additions to the library any time soon.
I REALLY wish that either the NI stuff was VST3.5 / VST Expression 2.0, etc., OR Steinberg could somehow get the library expansions for the HALion series going like the Komplete package has going for it.