Hands down…
Pryo - S: like no joke, Pryo is these hands down best over all bang for your buck spec. i not going to say they are the best at Each roll specs can fill but they can do just about every thing you would want out of spec.
Xeno fear stalling? Pryos got that in abundance, a good pryo not only denies areas with its greenfire but also just the threat of the push getting hit with flame wall can stall things out. I know as a Rav player (Hog strain for the most part) i fear the pryo, because i just know they going to get me killed by stalling aid.
Body recovery? yup Pryo are also pretty good at that too, just make a sea of greenfire extinguish a path to the body (also the body as well, never forget to do that.) and drag that poor lad back to the medics. Now i not going to say there the best but hot damn can make good work of it.
Fragging T3? again yes if they are on point with their Blue fire and got good extinguishing game ( or are good at using there firewalking ability), Yes they are not about to kill the queen or ravs but for every thing else they can do fine work. Again not the best but still quite good.
Clearing Ground? also yes, sort of. No were as good as the GL but depending on what you are dealing with good old sea of greenfire can do wonders. Got Node or sticky resin spam? then pryo is your man! also firing up to the door and slapping the xenos when they dare open the doors with bit of Greenfire can make pushing up the line into the resin walls much safer.
Again pyros are not the best in each trade but they can make things work with liberal application of greenfire! That’s really what makes Pryos the best they are a good all rounder while still having a area of excellence!
Edit: also never heard more true words