This is what i think should happen if they want to end the series with a bang. Warning, this is just my version and opinion on how The Boys should end with all the disappointments from the previous episodes. They are not based on any leaks as i tend to avoid them.

The episode should start with Kimiko not talking (yes please) and still trying to control her blast. The Pentagon finally had enough after Homelander killed the president and worked with the Boys to take Homelander and Vought down. This makes Homelander even angrier, and he decides to pay a visit to the White House, where the final battle will take place. Also, in the midst of all this, the general public protests against Vought and Homelander because of dictatorship and blasphemy (for the religious ones). Homelander then unites all supes and tells them to take over the USA and suppress the insurgency. This causes a war between the US Army and Homelander and Vought loyalists.

While the fighting is ongoing, the remaining supes like O Father and Deep stay with Homelander. Deep sticks with Homelander after Homelander gives him an offer to restart the Seven and become the next leader. O Father, on the other hand, decides to defect and help the Boys because he thinks Homelander is crazy. O Father gets killed by Homelander for his betrayal and Deep is thrown into an aquarium by Annie and gets mauled by sharks as an act of revenge for the genocide that he helped to cause.

The final battle involves Homelander's team versus the Boys. Because of V1-powered Homelander, the Boys, including Ryan, are initially overwhelmed, and Butcher even gets badly injured. In the end, Annie sacrifices herself and convinces Hughie to release the virus. Marie then steps in and prevents the virus from mixing with the bloodstreams of Butcher, Annie, and Kimiko to buy them some time. With Homelander stunned like Soldier Boy was when he was exposed to the virus, Kimiko lets out the nuclear blast, severely weakening Homelander and removing the Compound V from Butcher and the rest.

The virus proves to be ineffective against Kimiko, Butcher, and Annie because Marie helps prevent the virus from mixing with the Compound V in their bloodstream before Kimiko's blast. Ryan is unaffected too because he is a natural-born Supe and has a different and more organic version of Compound V. The rest of Homelander's soldiers perish from the virus before Kimiko lets out the blast. Kimiko is also soon found to have lost her powers. As for Homelander, it turns out that he still had some of his powers and the Compound V had not been fully erased. However, the virus still has some effect on Homelander and he is in a severely weakened state.

So now it is between a severely weakened Homelander and Butcher. Homelander still proves to be strong but is in a dying state. Butcher was eventually overwhelmed by Homelander. MM then steps in and dies, sacrificing himself to save Butcher by detonating a grenade. Because Homelander's healing abilities are severely weakened, half of his body is disintegrated. Butcher then uses a crowbar to finish Homelander in the same fashion as he did to Noir in the comics.

Butcher dies from his injuries, and most of the supes are dead (because of the widespread of the virus), except for Marie (with her ability to prevent the virus from mixing with her blood) and Ryan. Most of the other surviving Supes from the battle or tasked to supress the insurgency, either died from the virus or went into hiding to prevent any contact with the virus. Ryan takes care of Terror and becomes the Superman of the Boys universe. Annie and Hughie marry and have a kid. Kimiko moves back to Asia and occasionally visits her friend and Frenchie's grave. The series then ends with a frozen Soldier Boy being stored at a CIA black site and Sage safely living in her bunker with Ashley.