I have a feeling we'll find that outside of galaxies are even bigger, stranger, more impossible horrors that our galaxy was protecting us from.

Maybe, others who left first.

But space is big. [citation needed]

Remember: most advanced technological civilisation collapses occur in their home galaxies.

Move to be safe!

I presume these exist in every galaxy. Unless you’re suggesting we live in ships in the space between galaxies.

There are plenty of stars well distant from most everything else.

But yes, by the time we are equipped to leave the galaxy we ought to be finished with living on planets. (Which have been known to have their own problems... Cf. Deccan Traps, Yellowstone Supervolcano, Siberian Traps.)

That’s why in The Culture sensible people live on orbitals.

Weird that they always seem to keep them in orbit around stars. Seems like prosecuting the Idiran War would have been impossible for the Idirans if they could not find the orbitals.

They probably can’t produce enough AM to power them autonomously, so still rely on stellar radiation. More importantly, it’s kind of fun to have a large star in the sky.

Any Mind that couldn't cobble up a perfect sun simulation invisible to the Idirans would be a disgrace.

At least while we disassemble the various stellar objects and turn them into the computational substrate that powers our virtual reality paradise.

Disassembled planets should be enough for anybody.

The collision between Andromeda and Milky Way will be very disruptive, to say the least.

Not for most individual planets, excepting those that have a supermassive black hole come by. Odds favor you there.