I'm assuming they'll use the name Thunderbolts in "honor?" of Ross now and have Val (Julia Louis Dreyfuss) run the team. I've been rooting for more teams like this with Young Avengers and Midnight Sons at the top of the list with the Thunderbolts.I heard yesterday that a Thunderbolds movies is coming and they have a director attached, will be interesting how they will handle the Ross situation whether they recast or just not use Ross. Which then means they need to create someone for that position, and they can't even use Norma either. Even though I was never into this team I'm curious as it seems interesting to see a bad guy themed team for change.
Someone suggested brining back Justin Hammer for the Ross role which I think would great, as for the roster as I've said not familiar but it seems they're grooming U.S. Agent for it as well as Yelena, Nemo and few other newer characters. I don't expect to see Red Hulk though. Who else could they bring in or introduce that would be on the team?
There are a lot that could be included. You already mentioned:
Yelena (Black Widow)
but out there still are:
Batroc - could be alive...
and of course they could add any number of characters that have been part of that group in comics.