Alternatively:
Day 5, MC tells his mother that Eric has bragged to him about wanting to fuck both Ann's daughters, and Ann actually believes this and kicks the creep out. Eric retaliates by having her fired. Now, with no source of income the family struggles to stay afloat, and gradually turns over to the cams and porn. Essentially the same story, except the MC isn't just a pervy creep but potentially someone genuinely trying to support his family, at least in the beginning. Or presenting himself as such.
Eric's prolonged presence in the game is very much superfluous. He's just a source of particular kink, but absolutely not needed for the story to evolve the same way it always does.
That's rather the point, Max starts off with zero credit with the family, in many respects it's why Kira is in the story, she's Maxs "in" being part of the "female clan" whilst still willing to help Max. It's also part of the reason she drops out in the mid game as Max is progressing on his own without needing her insight and support anymore until it moves on with the loss of Anns job after Erics removal
So a scenario where Max approaches Ann and says Eric it Lolitaing you to fuck Alice and Lisa won't happen.
Now you could in theory do it via Kira which Ann would take more seriously but it comes down to control and I don't know that there's a version of the game where Ann wouldn't turn a blind eye to Eric with her daughters in order to keep Eric.
You see this in Lisas sex Ed and it's explained somewhat in the kidnapping story, so you would need to utterly recreate Anns character in order for that to happen and frankly she'd probably never touch Max with a ten foot pole if she was that different.
I see a point in your scenario and Max not being more supportive (and not buying a dishwasher) always bugged me especially when you have serious money just sitting there you can't spend
Erik however is responsible for a lot of Anns corruption Max takes advantage of.
Max sex watching in the room with Ann and Erik
Lisa Sex lessons
Erik and Kira sex
Ann wouldn't logically start sex ed with Max and Lisa, but continuing it after Eric pushes her into it is less of a logical leap
I also think the tone would get a lot darker if Erik leaves earlier Max, Alice and Kira rally to pay the bills then it comes out about Maxs website.
Anns feelings of betrayal would be all the greater after Max had been hero of the hour, but was basically selling thier private lives on the internet maybe not, I just think it seems a bit darker.
I suspect we won't see eye to eye on this

I accept you think he outstays his welcome (I actually dislike Eric the Red a lot less than OG Eric as he just seems a bit jaded and lazy) but given his removal is the trigger event for an act change I think there's merit in the establish a new normal while you corrupt the girls to your side before you remove your rival.
The nice thing is there's enough BB related games out there everyone is covered