The game includes a large SP aspect. But your point about the MMO, I don't see how it's valid, I feel this falls into an entirely new category. It doesn't have any of this levelling jibberish or pay to win shit, it seems to make itself very realistic an detatched from your standard cheesy MMO. Almost like the real world...
The devs are keen for this not to be branded an MMORPG, and so far, it is not.
I do understand your concerns about the tedium and grinding you might add of MMOs, but this isn't like others. You don't kill 50 aliens and get a big, badass carrier or something. You have to work together interacting with other players and form large tightly knit communities to pay for fuel and crew costs, other such trivial yet immersive things. This prevents the 'Everyone is a level 100 with the same badass ship' it's more like those guys work together and operate a larger much rarer ship and you find those who would prefer to venture alone and can only afford fighters, going for a life of a mercenary for larger corporations or being an independent trader.
You act as if there are set goals to reach level 50 or something, if you don't want to bother yourself with any of the economy or item acquiring just do missions or sign up as an escort, explore or mine - whatever the hell takes your fancy. There will always be something to do, it merely depends if you can be arsed to do it. I must point out the game is set where the great UEE Empire/Human Empire is about to collapse, similar to the Roman Empire's final years. After playing the game for a while the Universe could split in to 'East and West Rome', or the UEE could just collapse all together. The persistence of this Universe vs other similar games is its biggest bonus, and continued patching and ship additions. These should prevent the game becoming stale for a long time.
The game is a sandbox and the universe your oyster. Also i've played EVE. This will be nothing like that shit, trust me.