Another vote for Greg Egan. And I too really enjoyed the Children of Time series and anything written by Alastair Reynolds, although I don't think the genre is exactly what you're looking for. Finding modern, hard sci-fi really is pretty difficult.
I get where you're coming from with KSR's Mars series. I think Ministry for the Future was a better read, personally.
Also, I find that a lot of Crichton scratches similar itch to Andy Weir. Especially things like Andromeda Strain and Airframe.
You have disappointed De Morgan