I know we are still in betatesting and long way from any supplements which will add plently of these, but I´ll be damned if anybody havent already tought about some homebrewed ones. As I am skimming Only War from today I came with concepts of these:
Guardsman: Pathfinder (named about archeotype from Inquisitor LRB, your resident scout-sniper for people who like Mkoll and Mad Larkin but dont want to play Ratling, not the copypaste from those grimdark hobbits, one sniper advance and one more targeted to stealth) and Bodyguard (more CC and T guy, with Stormtrooper advances as I dont think they represent spec ops guy correctly (and want to remade him as in Ascension), maybe recreate him as colour-sergeant/standard bearer and you got the archeotype similiar to Jarran Kell)
Support Specialities : Gland Warrior (Lostock Augmentation as in RT Into the Storm, bit lost in other possible advances.. what I remember from older fluff companies of these guys are seconded to regular regiments), Navy Office r (combination of piloting we will hopefuly see later and liasoning with air support), Commissariat Provost (if anybody rembmer these guys from Last Chancers novels, military police types something like Guard Arbitrator with shotgun of course), Officio Sabatorum Operative (terrorist/saboteur guy, mentioned in Eye of Terror and Third Armageddon Campaigns and Last Chancers, specialities in sabotage, chem warfare and mass murder, maybe some mental traume resistance..)
Any ideas?