Hawkeye is a favorite character of many writers, and only was missing from the two ULTIMATE AVENGERS films due to the short run times of both. I have little doubt he would show up before long in an Avengers show.
Yost usually knows his stuff, but hopefully he can take it up to another level if he wants to match the standards set by JLU. Basically, every episode has to feel like X-MEN KINGBREAKER #4.
By default, though, unlike the X-Men, this show only has to surpass AVENGERS: UNITED THEY STAND from 1999, which is a very low bar. Hey, this stuff matters. WOLVERINE AND THE X-MEN had to stack up to the 1990's X-MEN and the 21st century X-MEN: EVOLUTION. This new AVENGERS show in 2012 doesn't have nearly as large a shadow to overcome.
My biggest pondering, besides whether Thor will actually be of decent power level for once (he was a bit of a puss in ULTIMATE AVENGERS, and did little more than take punches in HULK VS. THOR), and how they explain keeping Hulk around for long. Historically Hulk founded the team, but didn't stay very long; gone in canon in AVENGERS #2, although the Joe Casey "Year One" style Avengers mini from 2004 or so helped pad that out a bit more. I will be curious how they justify keeping him around.
Frankly, though, I often tired of the "dumb Hulk on the run from the military" angle to the character as I have been shown it about a million times, so it might be interesting seeing Hulk, well, NOT be that for a change. I mean, I enjoyed the Pantheon era in INCREDIBLE HULK, albeit that was "Smart Hulk". It would be fun if Hulk in this show had more than one personality; I imagine Fred Tatasciore would use his "Beast" voice for "Smart Hulk" if he had to. Much as Steve Blum is "Wolverine for life" as far as recent animation is concerned, I am sure Fred is considered "Hulk for life", which suit me fine. I am curious how they will cast the rest of the Avengers.
Thor was voiced by Dave Boat in the ULTIMATE AVENGERS films, and he's reprising the role in that kiddie Marvel Super Heroes thing coming on CARTOON NETWORK, but I am not sure if he will voice Thor in other stuff. Matthew Wolf just played Thor in HULK VS. THOR and may be returning for some other stuff. The Yost/Kyle team usually like to reprise or reuse the same actors they know are good or like or whatever. Michael Adamthwaite played Thor in a cameo in NEXT AVENGERS (he may be "best" known for playing my man Colossus in X-MEN EVOLUTION and Namor in FANTASTIC FOUR: WORLD'S GREATEST HEROES), and he was fine.
Justin Gross played Captain America in the ULTIMATE AVENGERS but many thought he sounded too "young" so I kind of doubt he would be recast, but who knows. I could imagine Grey DeLise asked to reprise her role of Wasp from those DTV's, though.
Hank Pym hasn't shown up in animation very often in the 21st century. Nolan North played him in the ULTIMATE AVENGERS films and is a popular actor in the current Marvel TV-verse. If they wanted to reuse his actor from MARVEL: ULTIMATE ALLIANCE, they could go with Jerry Houser. John Payne II played Pym in a guest stint in FANTASTIC FOUR: WORLD'S GREATEST HEROES but he's from Canada's Ocean Group troupe, so he is unlikely.
My "dream voice" for Iron Man would be Robert Hays, who played the character for the 1994-1996 era IRON MAN show (as well as in guest appearances in INCREDIBLE HULK, SPIDER-MAN and FANTASTIC FOUR shows of that era) and to this day is my de-facto Iron Man voice. Marc Worden played Iron Man in three of Lion's Gates' DTV's for Marvel, so he could be considered the most "experienced" actor to have played Stark in animation right now. Tom Kane played an elder Stark in NEXT AVENGERS and he's a dark horse candidate (especially as he also played Century and HOMER in that 90's IRON MAN show, too).
There was a preview teaser for this show that popped up on YouTube late last year for maybe a week before being zapped; the character designs looked better in motion, although Iron Man's helmet is still a little funky. Said teaser animation also confirmed Kang in his classic Kirby outfit.
