I focused on 10-Qs for the EDGAR filings module as you rightly pointed out - it seemed to be a good balance between implicit information and usefulness of the data. TBH I didn't actually investigate the other (many) patterns.
Having said that, I have really enjoyed Kai Wu's research from Sparkline Capital (https://www.sparklinecapital.com/), especially his extraction of the innovation factor from EDGAR filing texts. He's appeared in numerous podcasts, and they have all been super useful to listen to. Maybe someday when I re-investigate EDGAR filings and go further, I might target these signals you talk about here.