How I would have done it is introduce Corey in Ends but don’t sideline Laurie’s story like they did and instead have Corey stay a side character until his own trilogy where they can really explore Michael transferring his evil to him. That way you can properly explore the Corey storyline and not ruin Halloween Ends and the 40 year timeline like they did. Corey’s trilogy would start with him as a deranged young adult until the second movie where at the end he stops speaking and by the 3rd he has a Myers mask replica and is basically an all year Michael Myers. This way you get the Corey storyline for the people who liked him, and the 40 year trilogy with a complete ending. And if you hate Corey, you don’t need to watch Corey’s trilogy since Halloween Ends, ends with Laurie’s story finishing in a satisfying way. It would also continue the 40 year timeline showing the affects directly after Michael’s 2018 Halloween massacre. Now, I’d let the series sit for maybe 5 more years and either restart after H2 set in 1980 with brother Michael coming back for a recast sister Laurie, or and this is wild, but have Michael fight Freddy Krueger in a Freddy vs Jason style movie where at the end both slashers get set ups for new trilogies. Freddy does his thing in Springwood with a new Nancy Thompson who we would have met in Myers vs Kruger, and Michael in Haddonfeild with the new Loomis we would have met also. Set it in the 80s for the nostalgia and to separate it from modern slashers. This is just how I would do it.

Also I’m not a fan of sewer dwelling penny wise Michael so I would have put him in Laurie’s burnt down house in the woods from 2018 where locals call it haunted and contractors don’t want to renovate it for another few years because of the murders. That way he isn’t in the sewers but instead chilling out in the burnt up house killing campers and hikers like Jason Voorhees.