Are you looking for specific sounds for a particular purpose?
I quite find the PEPOfont and TetraPulse packs to be sufficient enough. I really like TetraPulse's drum samples, as well as the piano OGG sample. The other lesser known ones on the PxTone support site have some decent things; qPapers has some nice "string" instruments that make for great pads.
It really depends, though. Perhaps you'd want to mess around more with Ptvoice and Ptnoise to get the sounds you want? Another thing I did earlier when I only had PEPOfont is search up instruments I'm looking for, download their samples, export to OGG/wav if needed, and try to work with them in PxTone.
