The Starbrand wasn't a captive the last I saw, he was blowing up a builder ship, all by himself.
Face it, you have at least three, possibly as many as five depending on Carol's power fluctuations, Herald power level members of the team. Even the builders the elves have said they shouldn't be that powerful.
It's pretty much a foregone conclusion that they can't keep everyone on the team.
There's supposed to be a bit of a shakeup after Infinity, but I expect that it'll be dumping Ex Nihlo, Abyss, probably SpOck, and maybe Wolverine. Captain Universe may start going in and out more.
Starbrand and Nightmask look like to be a big part of Hickman's overall story. I doubt they'll be going far.
Hickman's supposed to have this thing plotted outthrough issue #63
supposedly. So I'm not thinking that the current team will be losing any of the big guns anytime soon.