[Whewt22]

Guessing the first through fourth espada, are espada wouldn't be much of an assumption. Just kidding I know you mean't vasto. However I disagree, the adjuchas class, like any other class -or even shinigami- entail powers that range from less fortunate ie. D-roy to fortunate Grimmjow. Who were both confirmed adjuchas.

I believe the espada is composed -or was for a better choice of words- of adjuchas and one gillian. With an exception to Barragan, based soley on overwhelming evidence throughout the series. Vasto is the pinnacle of menos evolution, it's highly unlikely he even has more than 2 let alone 5 as you've forgotten Wonderweiss in your top 4 assumptions.

Thinking back to all our confirmed adjuchas. They all had, with a few exceptions, which is normal, one thing in common. It's their animal or beast-esque features apon resurrection . Taking the page you linked with hitsugaya into consideration, anything composed of animal characteristics would of course not be human size nor human-esque as the corresponding picture makes obvious.

You have to take into consideration the attributes they gain apon releasing. People tend to confuse their arrancar bodies still being visable after releasing, as a vasto characteristic. Which isn't that case, that human-esque body was present before the release, you have to take what they gained into observation. Apon seeing Barragans release, as we saw, he lost all of his skin essentially becoming his former self, which is infact a human skeleton. His arrancar body was no longer visable and he became the epitome of vasto, based on the information given. Stark too would fall under this, as he has no visable features that would scream adjuchas, but im skeptical.

However nothings written down for us to bash our faces on, so we just scratch this up to coincidence.