Changes
President Ross invites Cap Falcon to the white house to thank them for intercepting some adamantium stolen from celestial island and Isaiah Bradley is invited as guest of honour
Under mind control by the Leader, Bradley attack the president who is shot by agent but rather than die he Hulks out revealing him as Red hulk as was teased in Secret wars
Rather than a detriment, this is a boon in public opinion and Red Hulk appears in public using nationalist anti alien rhetoric, declares celestial Island US territory and start legislation to imprison all aliens
Sam and Torres fight to prevent an international incident but Hulk is too strong and they cannot win, Sam detirmines that he is not strong enough - it's the low point of the film
Instead of giving up he decides to get help, recruiting She-Hulk who is investigating red Hulk independently, a former widow (from the black widow movie) working at the white house, Bucky, Skrull Warmachine, an Eternal, maybe Sersi investigating Celestial island independently, Joaquín, Eli Bradley, a mutant (there are already 3 mutants in the MCU), and an Asguardian, together they defeat Red Hulk.\ One of them walks up to Sam and tells him this is why Steve gave you the shield - because you are a leader - you know how to talk to people
Final change - The Leader's plan worked - he is left free and in possession of adamantium, world politics are destablised by Thaddius' actions leaving the leader a route to take power - we leave this open for a future movie, for fun we could end with him selling adamantium to a Canadian hinting at further mutant projects\

Connections
Resolving the President Hulk story that started in Falcon & Winter Soldier and carried on through to Secret Wars with the refugee plot lines
Mutants appear in the show and the adamantium connection to Wolverine/Weapon X
This version of the Avengers may not stick but it is the foundation of the Cap lead Avengers who will appear in Secret Wars / Doomsday
The Celestials body forms the Island and one Eternal appears
Bucky appears (not as a senator) and goes on to join the Thunderbolts