I’ll stick with Scripture all the same:
“Take no part in the unfruitful works of darkness, but instead expose them” Eph 5:11
“You adulterous people! Do you not know that friendship with the world is enmity with God? Therefore whoever wishes to be a friend of the world makes himself an enemy of God.” - James 4:4
While your kids may dress up like disney characters, you’re still lending approval towards the event, which is celebrated by death, zombies, and the grave. That your kids dress up differently does not change what Halloween is. An analogy would be “My kids celebrate Hannukah, but they only play with dreidles, they don’t actually light a minorah!” You’re still partnering with it.
Re: your points 2 and 3, we differ in our idea of ministry approach, so I can’t comment without risking a flame war.
1) H.P. Lovecraft, completely over the edge author and well-known madman.
2) Steven King famous modern-day dark writer.
3) Edger Allen Poe noted literary author and depressive.
4) Hamlet, Shakespeare’s classic and gory tale featuring necromancy and the death of almost the complete cast of characters by its end.
5) Ruddigore, Gilbert and Sullivan’s light opera, featuring paintings of Evil Ancestors whom come to life and communicate with the living, fortelling doom.
6) Our Town by Thorton Wilder, a classic play in which is set mostly in the town graveyard as the now deceased communicate to us descriptions of their lives.