I like the lineup, and I think it's actually a fairly beefy team. Captain Atom, Karen, and Kyle are all high-end powerhouses with lots of options beyond "hit really hard." You've got two big brains in Babs and Ted, Booster is a friggin time master, and Metamorpho can do practically anything, and can be an answer to nearly any problem.
But it is *way* too whitebread for today's audience.
So I suggest....
Drop Babs and replace her with Kate Kane or Cass Cain. They both bring Bat representation, they provide more diversity, and while neither are as smart as Babs, they have their own awesome skillsets to bring to the table. If Babs' intellect and personality are things you definitely want on the roster, then have her aid the team in her role as Oracle rather than Batgirl.
Drop Ted from the active roster and put him in a combat support role. Rather than be on the battlefield throwing punches, he can be in his Bug ship on the perimeter; providing intel, tech/support, medical assistance, evacuation, whatever. When sh*t hits the fan he can costume up and throw a punch but I think Ted could be much more interesting as a non-combatant team member. And it keeps the Blue-Bold bromance active. In his place, you could use someone like Jaime Reyes, Cyborg, Mister Terrific, or Steel.
You could replace Kyle with someone like Jo, Jess, John, or Baz, but I feel like this is the kind of roster Kyle would flourish on and the guy needs a home so I'm loathe to dump him. And no, I don't count his "half Mexican" retcon as representation; it has almost never been mentioned and has had zero impact on how Kyle is written or drawn.
The team does need a big name sales draw, though I dunno how effective that strategy is these days, and the team already has characters from a bunch of major IP's. Maybe someone like the new Wonder Girl, Yara Flor. She seems to be making a lot of buzz. There's also Naomi, and...if a big name character is what you're after, gods help me, Harley Quinn (just kidding).