I have to wonder... just how avian are the Hissho?

By in-game appearance, they are very... human looking. Now, don't get me wrong, I love their design, but I have to wonder... It's safe to say, at some point they lost their wings. They probably still have some kind of feathers, at least as sort of hair (the old Endless Space art of them had bodily feathers, not sure how canon it still is, design-wise). They have human looking hands which may or may not have talons. Body-wise, they have human-ish silhouettes, to the point where, looking at Tsuyu, I can clearly tell she's female, from a conventional human point of view. Now, looking at the female heroes, I can pretty confidently say... they have breasts. Here, as such, comes my question:

Are they more avian, or more like a mammalian with avian features? If they have breasts, do they have beaks? If yes, why have breasts, since it's pretty hard to breastfeed someone with a beak... Now don't get me wrong, an avian bipedal humanoid in fiction can range from the D&D Aarakockra, which are basically bipedal birds with arms, to Mass Effect's Turians, which are very birdy in physiology, though not conventionally bird-shaped (crests and some kind of beaks, alien bird-looking chests, alien bird-looking feet), to DC Comics Hawkgirl, which is basically a winged human, and I really REALLY dig the Hissho design in ES2, being my second favourite race in the franchise, looks-wise (Vodyani come first, Cultists of the Eternal End come third), But I am just curious. A mammalian-avian-humanoid alien is very interesting as a concept to me and is the feel I get form them in their ES2 Incarnation.

Are they more avian, or more like a mammalian with avian features? If they have breasts, do they have beaks? If yes, why have breasts, since it's pretty hard to breastfeed someone with a beak... Now don't get me wrong, an avian bipedal humanoid in fiction can range from the D&D  VidMat Mobdroe Aarakockra, which are basically bipedal birds with arms, to Mass Effect's Turians, which are very birdy in physiology, though not conve word counter ntionally bird-shaped (crests and some kind of beaks, alien bird-looking chests, alien bird-looking feet), to DC Comics Hawkgirl, which is basically a winged human, and I really REALLY dig the Hissho design in ES2, being my second favourite race in the franchise, looks-wise (Vodyani come first, Cultists of the Eternal End come third), But I am just curious. A mammalian-avian-humanoid alien is very interesting as a concept to me and is the feel I get form them in their ES2 Incarnation.

issue solved!!!

I believe that the Hissho were way more bird-like originally. However, they were tampered with by the Endless to be more "human", like them. This was done so people could enjoy their bloodsport matches more in the arena. 

So for instance, they lost their wings.