Aurora

I loved all of Seveneves, and hate Three Body Problem. The biggest difference in theme being, optimism that humanity can overcome any obstacle and flourish. If you want more in that vein, see: Aurora - Kim Stanley Robinson Project Hail Mary - Andy Weir Delta-V - Daniel Suarez

https://en.wikipedia.org/wiki/Aurora_%28novel%29 Is it really so wise and ethical to launch a mission to another star system? With KSR's usual deft handling of complex systems.

By far the best is Simon Funk's "AfterLife". The mystery keeps you on the edge of your seat and the tech jargon and concepts are both detailed and correct which is a rare thing for any fiction. Also, Charles Stross - "Accelerando" Daniel Suarez" "Daemon" Kim Stanley Robinson - "Aurora" Tobias Buckell - "System Reset"

Most of the other books I'd recommend in this area are mentioned already, but I'll add Aurora by Kim Stanley Robinson. The primary narrative is from the pov of a generation ship's A.I.. You get to see it learn over time and with it it's vocabulary. Since it's a ship it gives KSR the opportunity to do some very fun info-dumps on the situation. Probably one of the most thought provoking pieces of scifi I've read. I'll also recommend Accelerondo, and Seveneves.