So I was a little surprised that my first play session of Stellaris lasted four hours. I was learning a lot and made some mistakes but overall it was great! I came back to that same playthrough another night and played for another few hours before stalling out in the mid-game as all the alien cultures' borders filled in.
I immediately jumped over to a new game with slightly tweaked settings (for fun and variety) and proceeded to spend another six hours of so in that game. And this time I made my own alien race! That part was super fun. The second round was much better since I could apply everything I learned the first time... but again I found myself stall out in the mid-game without much to do.
I looked around online and saw most people suggesting fighting with neighboring species to gain territory at this point in a playthrough. I've never liked doing that in my 4x games so I mostly ended up sitting there researching technology until I stalled out completely.
Apparently there are endgame events that are a lot of fun if you have the patience to get to them but I haven't seen them.
But not all hope is lost. This is a Paradox game and they're very well known for expanding and adding to their games over time. There are already two expansions for Stellaris out as of me writing this. I think I'm going to shelve Stellaris for the moment and wait for them to release some more expansions for it. If they put out expansions for non-miltary mid-game choices I would be all over that. Think things like trading, economy, and espionage. It feels like some of the groundwork is laid for this stuff already, it's just not implemented yet.
Having already gotten 13 hours of play time out of Stellaris I definitely don't feel like I wasted my money. I'm perfectly happy biding my time to see what else they do with the game in the future.