I'm enjoying To Sleep in a Sea of Stars by Paolini. Though it is a bit long, it has lots of character development and I thought had a similar vibe to the Expanse. Also available as an audiobook which is excellent.
On the lighter side there is The Long Way to a Small, Angry Planet by Chambers (1st of a series) which I think are all excellent Adult/YA Space Opera and more in line with the Weir books.
I forgot about the We are Bob series, but I also really enjoyed them.