"JR jr is drawing the spoilers, so leaves them open. Anyway, the way the cape is flowing hides everything. "

Well, the large forearm could be Moon Knight's armor on the arm. 

"Well, the large forearm could be Moon Knight's armor on the arm.  "

Moon Knight.It has to be the Moon Knight.

Probably Moonknight

Moon knight or Sentry

For one section it would. He has a large plate on his forearm. Why they drew the cape that way. To hide any detail, same for the reason they drew the first one that way. 
 
They also removed as much detail as possible.

It's... Doctor DOOM!!!!

it looks alot like that kree  ronan the acuser dude to me weirdly lol or even possibly the hood

if we could get a clue as to if they are good guy or reformed baddies it would help. i dont think its the scralet witch (doesnt look like its female) task master maybe (cuz it looks like it has a hood) sentry doubtful (i believe he'll be the big bad guy at the end of siege everyone has to gang up on)
would be great if the secret avengers were undercover heroes posing as villains the same way the dark avengers were posing as heroes. cuz why would u need secret avengers in the heroic age unless their keeping the secret from the villains. just what i think.

It has to be Moon Knight Redemption is his whole angle right now he stopped murdering and everything

"

CLOAK BITCHES 
 
u know that black dude thats like a living shadow hangs out witha hot chick white outfit throws daggers

"

its cloak you dweebs look at the comment

Im hoping for Moonknight...but... don' t think so

" Im hoping for Moonknight...but... don' t think so "

I'm thinking either Wanda or Doom.

Farfetched, but Brother Voodoo?

Also see that super long thumbnail. Woof...

I see the cape and I think of the old Black Panther costume, but the redemption part doesn't fit. Except maybe payback to Doom. I am going Moonknight or Taskmaster,

Black Panther

looks like he has claws...

Sentry.

Important details 
 

It's the Hood.

Green Goblin Earth 1610 style. 

Its obviously The Beyonder

I have to say Moon Knight. The arm which is exposed has too much muscle to be Scarlet Witch... unless it's poorly drawn. ;)

Your forgetting about her glove. Since they removed the detail, the overmuscled arm could be her glove. Her gloves are a little baggy.

Gotta be Moon Knight!  Better be Moon Knight.  Someone's dying if it isn't Moon Knight!

I say its moon knight
 
The cape and quote along with reasons to leave her on the shadows fit Scarlet Witch but the rest of the body doesn't

its either Moon Knight or Brother Voodoo...  100% sure...  The last picture was Beast...  Should be an impressive line-up!  THAT BEING SAID, am i the only one who was kind of hoping there would be 1 Avengers title kickin' off the "Heroic Age"???  Like Amazing Spider-Man, it could come out a couple of times a month...  I love the notion of ONLY 1 Avengers title...  Secret Avengers sounds like ANOTHER X-force rip off...  Kind of dilutes the magnitude of the cancellations/relaunches don't it???  
 
THERE SHOULD BE ONLY 1!!!

"I see the edge of what looks like a hood. I say Taskmaster. "

doubting this but putting it out there anyways.
could be Prodigy. he's striving for redemption, has shoulder pads and his cape is always
a bit overdone, same physique, plus Marvel has been promoting him alot ever since his guest
spot in MUA2 for some reason. he also had a fairly important role in Civil War.