Paradox's Stellaris takes grand strategy to the vast vacuum of space
It's brand new territory for Paradox Development Studio, which built its reputation on deep and complex historical simulations--from Crusader Kings II (that game with the incest) to Hearts of Iron (that game where you feel bad playing as the Nazis) to Sengoku (that game nobody remembers).
Science fiction seems like an interesting shift for Paradox, as it gives the developer a whole lot of freedom to work with. Crusader Kings II, Europa Universalis IV, et cetera were constrained both by history and by geography--you can't exactly rewrite Earth's past, nor redesign its map.
By abandoning Earth, Paradox gains freedom. Stellaris consists of procedurally-generated star systems, which should make exploration quite a bit more interesting.
Alien races you encounter are also unique and procedurally-generated, according to Paradox. The game will work a bit different from the studio's previous games, where you could choose to play as any country you saw on the map. In Stellaris, you'll choose from a predetermined set (Paradox says "numerous") of alien races, and then the game will create your enemies from scratch.
Paradox promises an "advanced diplomacy system" to go along with all these alien races. Personally I'm holding out hope some of the races you encounter don't speak English/a common language, making it either impossible or improbable for you to communicate until certain technologies (Babel Fish) are discovered or enough time has passed for language cross-pollination to occur. A man can dream.
There's also a ship designer, though it's apparently not quite as robust as Galactic Civilizations 3. Paradox told me it's "modular in a sense--ships have different sections where you can slot things in," which sounds maybe a bit like FTL. I'll wait to see it in action, though I am excited you can customize every ship down to the smallest civilian vessel.
We haven't heard a release date yet, but I'd assume the end of 2016 at the earliest--Paradox already has Hearts of Iron IV slated for early next year.