The space emperor calls the greatest engineer in space to his palace. He will die soon...

The space emperor calls the greatest engineer in space to his palace. He will die soon, and he wants a grand monument to his time as emperor to be built. He wants it to be super impressive to everyone, built and left in space, and put in a system that people have to pass through a lot so everyone will see it constantly for the next thousand years. It needs to be at least the size of a small planet to be big enough. He understands that it won't be finished while he's still alive, but he still needs to approve it.

What can the space engineer suggest that will satisfy the space emperor?

The Ship is All. The Ship Moves.

Better clothes.

The United Empire needed that overhaul in aesthetic for Endless Space 2.

how about a golden Palace covering half the planet?

A single von neumann machine, programed to adapt and enhance itself as it devours all matter in the universe to create an infinite monument.

The engineer did not like the Emperor, enjoy the space plague legacy.

A huge semi-opaque golden orb that orbits the sun in such a way as to cast a golden glow onto the planets below at least twice a day to remind the people that the Emperor is always watching over them.

Make his image appear on the front page of every search engine in use in the empire.

A machine that makes him not die.

A massive phallus.

Not made of any precious material though, don't want a later generation to just nick and re-purpose it. You just want a big phallus shaped planet-sized rock floating around.

Heck maybe allow life to grow on it. Name it after the emp though.

A giant war-robot shaped like the emperor.

I gigantic beard, made in the image of the space emperor's glorious beard

There's only one answer and you know it.

The vodyani ships have by far the best aesthetic.

a moon sized disco ball orbiting the planet in such a way that the planet it orbits is having an eternal wake party for the space emperor

A bigass golden toilet with his corpse on it.

I'm partial to the Lumeris commercial shipping style.

But I do like the ships shown so far. I'm a bit bummed the Hissho aren't playable this time.

An artificial planet in the shape of diamond. The pyramid itself will be populated by the most deadly forces in the galaxy, which is guided to be more deadly by a thousand competing AIs. Some control robot armies, others genetically engineer creatures of nightmares. At the center of the pyramid, only unlock able after destroying all the AIs, is a plug in to change the pyramid into a fleet of ships controlled by the user, and crowning them emperor. Propaganda will spread this challenge throughout the empire for various generals and others who would fracture the realm to gather and use their armies to beat this challenge.

Only the emperor and the engineer know that the uplink will just download a copy of the emperor into the user, thus giving the emperor a new life, with a fun twist.

Ripping off tau stuff but more human?

How about a giant psychic bonfire visible in hyperspace for 100,000 light years in all directions?

...

I'd go with a feelgood epitaph of pure marble, protected by various forcefields, with the carved autobiography of the emperor on it, translated in all the languages on the empire. But I guess that's a safe and boring pitch.

The greatest legacy a man can leave behind is what he did. His empire, his research, his accomplishments. Everything he has done with true effort.

Both evil and good. For a legacy is something to be remembered by.

Engineseer can't do much at that point though.

Continue research on ancient technology and help make technology great again