Planet Upgrades.
Not upgrades to put on a planet, but the ability to literally upgrade the planet itself. Ships that bring down asterroids and terraform them on the surface to increase planet size...basically, the ability to make every single square on the surface of the planet usable through terraforming and research that's a veritable paradise.
The ability to build self-sustaining ships at low levels, (can go any distance, carry all things needed to support life)
Genetic Engineering Techs: Let you improve your species
Boarding parties: Capture enemy ships instead of destroying them
Also... Mega-techs.
Dyson Spheres (a sun-enclosing 'space station')
Ring Worlds (like a dyson sphere, but only a single ring, spun for centrifugal force, still ridiculous amount of land able to live on
Station-worlds (Keep adding to a station until it becomes a mechanical world unto itself)
Planet-destroying weapons
Sun-destroying weapons
World-building machines
Very late game-tech that lets you breach the dimensions (allowing a permanant wormhole to connect to another map... probably where every race you've defeated is dominant, and your race doesn't exist any longer.)
Ship-teleporting stations or stargates (teleport to other equiped stations)
The ability to continue post-trancendence with awesome stuff.
The ability to travel back in time and change the past (oh.. wait... load last save, different choices... nevermind.

)
A timed-game option: Game only lasts a limited number of rounds, strongest civilization wins
A 'no enemies' option: Really toughen up the micro-management, no enemy players. Basically turn Gal Civ into a galactic sim-city as a result.
A 'no micromanagement' option: All races progress down a set technological path and build order (except for ships) - All combat gameplay
multi-player action, even if its on the same computer
And finally...
A giant ball of dancing sushi event.... okay, just kidding on that one.