The first one appears to be a classic with nicely-balanced features.

I don’t like any of the choices, although your original white door does stand out.

You say it’s a dark porch, so why do a dark door?

Of what you show, I wouldn’t mind the third choice but with a white door.

third option- the white trim brightens it and ties it in with the rest of the house, the door can be a fun color or natural wood.

eld - what do you think would suit? Open to ideas :) I don't want to do a white door - have had that for 15 years, time to move on. I would go for a grey door but unfortunately all of our downspouts/eaves etc are chocolate brown

My choice would be a door with glass that mimics your windows a little more. Maybe something similar to this 6-lite door. A light color would help give it more focus. Sorry the photo won't enlarge.

I like your third choice the best.