The Ending Saved the Film

Agree with some of your points, although I felt that H20 was a much more satisfying ending overall, particularly the last scene. The second act in this movie is definitely the weakest part and its depiction of Michael is not completely consistent with the character from the original. It would have been nice to see him stalking Laurie's daughter and her friends as they're walking down the street, as that part is clearly meant to recall a similar scene with Laurie, Annie, and Linda.
But overall, I felt it was a solid slasher sequel.

The ending was ridiculous. The remote-controlled, motorized kitchen counter, the instantly-activating jail bars, and the flammable gas setup were like something out of a 1960s James Bond movie. Who did she call to build/install those gizmos? Her local Hollywood prop department? Also, that "trap" was oddly specific, i.e., at some point in the past she imagined a scenario where Michael Myers, who wasn't scheduled to ever be released from the funny farm, would be in her hidden basement, but she would be outside of the basement within reach of the rapid-fire jail bars activation button, and then based on this imagined scenario she dropped a lot of cash to have it built/installed, and what do you know? She must be the next Miss Cleo because it ended up happening exactly like that.

Also, her actions were stupid too. If you have a basement with firearms and plenty of ammunition, and a killer is in your house, you simply stay in the basement ready to shoot anyone who opens the entrance to the basement. Going looking for him is stupid, because you forfeit your huge advantage of being ensconced.

As a side note, why would she have a Winchester model 1873 rifle? Those are expensive specialty guns that you would typically have to go out of your way to find, and that applies to the modern Italian-made clones too, which start at about $1,300. The normal market for an M1873 or clone is collectors and people who compete in "Cowboy Action Shooting" competitions. For someone who just wants a lever-action rifle for home defense, a common-as-dirt, affordable, and more reliable Winchester model 94 or Marlin model 1894, especially chambered for .357 Magnum or .44 Magnum, would make a lot more sense. Those calibers are both far more powerful than .44-40 when fired from a rifle-length barrel; they are far more readily available, and there's a wide range of defensive-type ammunition for them (SJHP and JHP bullets).

I would like liked if they just shot him and killed in directly at the end and confirm he's dead.. I can imagine yet another sequel and explaining how he (michael) got out of that burning trap room.