How close are you to a 5/65?
Rank up the Loki, he'll make it easy to take down the final ultron boss. Also, the mordo would be a good choice as well for the resistance paths in 5.4
Honestly, you have everything you need in terms of your roster. You just need to practice a bit more. Plan your paths.I’d 5/50 Corvus and 4/55 Domino.AA is a solid consideration as well. Rulk too if you take up Domino.