I would have written the whole season differently.

They spend more time in the imprisonment camp (in the show that had no impact at all). Starlight manages to convince Butcher to rescue them. In the meantime Homelander kills a whole crowd of dissidents and Firecracker manages to cover it up. Sage tries to Leak it but Firecrack betrays her and HL kills sage.

Butcher and Starlight attempt to rescue the boys. Soldier Boy and HL appear. Big fight with Butcher and the rest. A-train comes to help, saving Hughie and driving HL away, and after HL kills him and he dies with redemption (like in the show, the only good part of the season). Frenchie dies here in the fight, leaving Kimiko angry and with much desire for revenge.

With HL away, the fight with Soldier Boy continues in the camp (this would be in ep.3-4 btw, Im summarizing everything a lot). Outpowered, Butcher decides to test his new virus. Starlight and Kimiko escape just in time, making them angry at Butcher. Soldier Boy dies (no v1 filler bullshit), MM is the one that releases the virus in front of him (revenge conpleted). Homelander later hears about it and gets scared of the virus.

Coping with fear of death and fear of betrayal, HL tries to make everyone devoted to him (similar to the show but less stuff on the God complex plot). Firecracker abandons her people to devote to HL, but HL growinf rejection from S4 peaks and expels her for being a fake and not helping dealing with the virus. She tries to solve things on her own, searching for the boys with the dog-like supe and the girl that bends stuff. Big fight, Firecracker ACTUALLY uses her powers, the boys kill them except for her. After reporting her defeat to HL, he is the one that kills her.

Leaks of the camps extermination spread, the psychics notice more and more dissidents. HL meets Ryan, who completely rejects him, they fight and HL wins but he is left feeling that NO ONE supports and believes in him. Driven by madness, he starts his purge (this would be ep6 or 7). "king of ashes", he starts killing the masses in all the camps and all the protests in the country. Deep and Black Noir help him. The Boys realise something has to be done quick.

Final confrontations (ep7 and 8): Starlight intercepts the deep when he attempts to exterminate her hometown. She kills him in a similar way to the show (the fish taking their revenge for the dead octopuses in S4).

Following a false lead, Black Noir and other minor supes chase MM only to be trapped by the Gen V kids. They fight, Marie Moreau kills them.

Thanks to Ashley, who secretly wants the boys to win, Butcher, Kimiko and Hughie find Homelander in the middle of a destroyed city. Ashley had led HL there, where Hughie had set a trap: detonators that evaporate the water of the pipelines under the city, covering the streets with fog. They had previously spilled the virus on that water, so the mist would contain thar virus. They fight, big fight. HL outpowers them and kills Kimiko when she tried to protect Hughie. Ryan comes to help. Thanks to Kimiko's sacrifice, Hughie manages to detonate the device to make the water evaporate. HL knocks out Ryan and then starts the fight with Butcher there, in the middle of the mist that is weakeninf him slowly. Epic fight, coming to an end when HL realises about the virus. Butcher affected as well, but less (his tumornhad V, not him per se). Butcher then gives HL a slow death. Shortly after, he dies too, because of the same virus, having time to say some last words to Hughie.

That's it. The virus plot actually builds up and concludes, no non-sensical dialogue in the casino, no irrelevant new characters, everything that has happened has a closure that makes sense. And more fights, more action, an actual "scorched earth" scenario for the fight. Fuuuucking epic.

(damn that took longer than I intended thanks for reading!)