I highly recommend anything by Adrian Tchaikovsky. His themes and ideas are deep and fascinating. https://www.amazon.com/stores/Adrian-Tchaikovsky/author/B002... (Children of Time Series, Dogs of War and City of Last Chances are great). Him and Dan Simmons are my favorite new(ish) authors. If you haven't read the Hyperion quadrilogy, it's my favorite sci-fi series ever.
I hate to be that guy, but I find Andy Weir's books to be very simple and 'light' sci-fi. Fun reads but usually suffers from the protagonist being a genius and smart aleck. No deep themes or characters. I never understood the crazy appeal after reading all of Asimov and Arthur C Clarke. Personally I want giant themes, huge space operas, complex characters and long storylines!