Squadron Roster
On pages 18 and 35-36 we see that there are seven Hibernaculum tubes filled. Page 18 gives us the clearest view. They are, from right to left: Black Archer, Foxfire, Thermite, Pinball, a figure seemingly wrapped in bandages, and Tom Thumb. On page 36 we see that Blue Eagle is to the right of Black Archer.
Who is the figure in bandages? Nighthawk? No, the late Dr Decibel. He is to be taken to the Hibernacle at the end of Squadron Supreme #10
This fits in with the character of Nighthawk. In rejecting the Utopian plans of the Squadron he no doubt felt bound to reject any offer they might have given for life extension developed from their plans. Kyle Richmond must have changed his will to specify no hibernation.
Why did Gruenwald feel it was necessary to hide the identity of Dr Decibel, or at least not confirm that it wasn't Nighthawk? (Neithers injuries were of such extent as to require full body wrap.) I can only guess it was to keep the secret for a later plot point.
Power Princess wears a golden helmet and golden armor plates on her chest, arms, lower legs, and skirt. A reaction to the pummeling she recieved in Squadron Supreme #12?
Dr Spectrum is wearing his facemask again, to hide his monochromatic features.
Lady Lark adopts Blue Eagles wings as a tribute to him.
Arcanna adopts Moonglows appearance to accompany the team. See also comments.
Arcanna is casting an illusion that she is Moonglow. On page 51, when she must use her magicks to seal the spacecraft breach, the waves of energy passing around her partially reveal her Arcanna outfit (and baby carrier). However, on page 58 and 59 she enters into mystical communion with Professor Imam without concern about revealing her identity. With everything that goes on since that she keeps the same appearance only a slight change on page 67 when she disperses the headpiece and reveals Benjamin in his baby holder.
I am of the opinion that both outfits were illusions. Arcanna has been written in the limited series as of the Wiccan/nature magic style (as opposed to the traditional Dr Strange magic artifact style.) I believe she would be more comfortable in the nude. See, for example, page 74, whether that is her physical body in Nth space or her astral projection (self image) in Benjamin's mind.
Out of respect for public sensibilities she cast an illusion of a costume around her (a fairly permanent spell that would not end if she were knocked unconscious, much like the hiding of Squadron City.) The overlay of her Moonglow illusion, however, was disrupted by concentrating on other magics and the spell reverted to it's "default". To help Professor Imam without revealing her identity she changed the default to Moonglow's costume, which she has worn since.
Versus
Power Princess vs Redstone
She is hampered by the fact that she does not want to trash Tom Thumb's
laboratory. Redstone seems to be getting the better of it until Hyperion
interupts them.