It's been a while since I've played an Avengers team, and I really didn't get a chance to play a lot of the figures from that set. I like Wonder Man, the big lug, and he's a good price for a 300 pt team, so I thought I'd build around him.
300 pts Restricted - Avengers keyword
Wonder Man (AV) w/Protected
Hawkeye (AV) w/Armor Piercing
Mockingbird V w/Pummel
Alpha Flight ATA
"He's thrown a kettle over a pub - what have you done?"
My only suggestion would be, if you have it, the LE Victor Shade in place of R Vision. Dump all feats to make room for him.
Protected's a crutch, Hawkeye won't need AP if you play him properly, and Pummel is nice but not critical.
LE Victor has an 8 range, 10 AV, 3 dmg Stealth and Perplex to start. Mid-dial, he picks up the 10 AV again, with Running Shot. He never gets super strength or impervious. He's snipe and support, a secondary attacker.
Have Wondy carry Mockingbird into battle, and let Hawkeye and Victor pick off the stragglers.