It's funny, a few short years ago in the comics they more or less took a page from the Incredibles and aged up the 2 kids (Franklin and Val) to have them as functional teenage members of the F4. Basically was looking like the F6 for a minute.
As far as Sue... in truth, they've often struggled with what to do with her imo. Basically the Jean Grey dilemma of outside of being the hot wife that all her husband's frenemies want to fukk, there's not much going on there. Super powerful but basically mother hen/neglected housewife status, while her husband [who isn't that interesting either] at least gets to hang out/beef with interesting people or walk the moral tight rope with his experiments that lead to calamity.
Tho tbf, all four of them can feel like caricatures. Which is why who the actual focus is on isn't as important for this IP as having an overarching story that gets people invested in them, and not just in Doom or on Reed joining his Illuminati friends.