I'd agree that the helmets are detailed enough and different enough from the basic ones, that they'd make better "squad leader" helmets (or "veteran squad" helmets) than having the whole army have them.
Same applies to the Imperial Fists ones. Laurel wreath and "knight-style helmet with airholes" - that's the sort of thing you'd see on an Emperor's Champion, not on a regular guy.
The Imperial Fists article did say that the transverse crest helmet is for Sergeants or Praetors - same would apply to the wolf helmet with topknot.