My lazy guess is Reed and Sue, but I am hoping not. Too early for Reed to self-implode, yet. I like that the FF are back together, but they are relegated to low status, like the Avengers have been. I want that to play out a lot longer before the powers that be start to reverse that trend.
I’m anticipating sometime that Doom would join the FF. Maybe like in 1997, when Doom married Sue and Valeria becomes Dooms daughter, that happens, and Reed is out of the picture? That was an alternative reality, but I can see the development of Sue leaning more towards Victor, and away from Reed. This I can see happening.