I agree. It might have Avengers in the title, but like Hickman's Secret Wars I'd like it to secretly be a Fantastic Four event. I think Secret Wars is the best possible opportunity to prove that the Fantastic Four are worthy of mainstream attention, likely the biggest opportunity they will ever get to appeal to an audience of multi-millions.
I think Avengers did an intelligent thing buy narrowing down the cast for most of Endgame. I suspect, and even hope, they do the same with Kang Dynasty and Secret Wars. I'd like Kang Dynasty to involve Moon Knight, Kamala, Blade, Shang-Chi, Deadpool, Wonderman if that's still on the docket, etc but I personally want Secret Wars to focus on major players like Endgame did, with a couple of unexpected surprise choices.