He's pretty much the only sequel trilogy villain who hasn't really had any EU backstory stuff yet. Hux's backstory is covered in many of the books (Basically he took over from his father as a leader of the FO), Ren of course has a ton, Phasma of course has her own origin novel etc.

Pryde is fairly unique in that he's a veteran of the original Empire, rather than the rest of the FO leadership apart from Snoke who were fairly young. Wonder if there's any chance he could show up in Marvel's series? Soule kind of likes to put sequel trilogy references whenever he can, with Kylo Ren hinted in his Darth Vader series, and of course the Damerons showing up in the monthly.