Here's the North Bennet Street school Preservation Carpentry answer. I've only been doing this for about a year so this is by no means the only way to tackle this.
If using chemical stripper, wrap in cellophane and let it sit wrapped for a few hours to increase effectiveness. If you use heat after chemicals, make sure you've removed the chemicals to make sure you don't get any nasty gasses.
Heat helps a lot, especially in conjunction with mechanical methods. We'd have a heat gun and our assortment of scrapers. Heat, scrape, repeat.
EDIT: Don't use heat if your door also has window panes in it. The heat can break glass that's glazed into doors or sash.
For scrapers, we used ~3" wide straight scrapers for flats, profiles (I.e. tear drops, triangles, rounds, etc) to get most of the profiles, and finish off with old dental pics for really stubborn spots and testing for rot. Channel lock sells a 4 pack of essentially the same thing.
And we were always told "if it's between scraping off the wood and leaving a small amount of old paint, leave the paint and prime over. Always"
Kind of hand in hand with that, you should never sandblast wood (unless maybe that's a specific look you're going for). It will wear the different parts of the wood differently. Even baking soda can damage a wood door if you're worried about keeping it as pristine as possible.
You can also sand if you have small sanding profile blocks. Spray with water then sand to decrease risk of putting anything nasty from old paint into the air.
One word on PPE, if the door is from before 1978, assume there's lead paint. Respirators, eye pro, tyvek suit if you're really cautious.
