Charles de Lint has some fantastic urban fantasy novels/novellas. I really like CJ Cherryh's space novels - you could start with a fast read like Pride of Chanur or Merchanter's Luck before hitting longer novels like Downbelow Station. James P Hogan writes some good "hard" science fiction (iirc, he used to teach physics); he's probably best known for the Giant's Star trilogy (books 4&5 came later and I don't count them), but I like Thrice Upon a Time. I like Ben Aaronovitch's Rivers of London series (the earlier books are better, imo) and Naomi Novik's Scholomance series.