To me, Agatha's presence introduced many problems:

1. The entire Darkhold book which was both yet another Magical McGuffin and caused lots of issues eventually in Multiverse of Madness. Beyond being more extra "lore", it also felt repetitive towards prior MCU works which always revolved around a special McGuffin.
2. It resulted in a very standard big effects driven finale when something more intimate and grounded would have been befitted the show and it's subject matter.
3. Morality wise, it just kinda complicated things. Yeah, you could say it added more complexity but the show's story about the lengths people go to when they're grieving and the moral lines that can be crossed is sorta muddled when you have this twist villain character who poses a genuine threat and has even been doing certain bad things all the time. And who ends up being the final boss rather than Wanda, who caused the entire situation to begin with.
4. On her own, Agatha just didn't have much going for her so cutting her wouldn't mean that we would have lost some amazingly three dimensional character.
5. You could have avoided complaints about side stepping Wanda's own questionable actions and more smoothly set up another story either for her to be redeemed or for her to go full villain.

A stronger conclusion for Wandavision would have been a very simple one. The illusion gets broken, Wanda remembers why she's doing this maybe with the help of another character who's not a villain and then there's a confrontation. Maybe she's taken out of power and restrained. Weirdly I'm thinking of Falling Down as an inspiration, specifically with the final exchange between Foster and Prendergast.

Something like (putting Howard in this position for now):

Tyler Howard: We've got an entire prison to lock people like you in, maybe we should have done a better job years ago......

Wanda: I'm the villain?

Tyler Howard: Absolutely.

Wanda: You don't know what I've been through! I needed this! I couldn't go on otherwise!

Tyler Howard: Everyone's been through what you've been through. And even if they've not, do really think that gave you any special right to enslave people and make them play out your self obsessed perfect fantasy? If you do, then that's why we're taking you away.

Ending the show on a note like this, without a big fight even, would have had plenty of weight and it would have been daring. Even if you wanted to include a big fight, it could have just been Wanda vs the Military or Wanda vs someone sent in to capture her. It would have been smoother also, allowing for us to naturally end the miniseries in a manner that's not cluttered.

P.S. Also, White Vision should have been cut or just incorporated better, don't give him a Stage Exit and not return to him for years.

"It is your destiny to destroy the world."

Agatha's line in the finale. I think Wong said something similar in Multiverse of Madness, that she's prophesized to destroy the cosmos. Though nothing came of it in that film, as Wanda had no desire to rule or end the Multiverse there.

Is this destiny thing going anywhere? That line couldn't have been put there for no reason. I'm guessing the Scarlet Witch lore in general will be explored more in-depth in the Agatha show, and the prophecy will be expanded on.

If this plot thread isn't just swept under the rug how do you think it could play out? Maybe the current Multiverse is so deeply flawed it needs to be replaced by a new reality and destroying the old world is Wanda's role? What do you think?

Or Colonial Street as it's officially known as. Such a beautiful suburban neighborhood!