1. The Liaden books, by Steve Miller and Sharon Lee. Space Opera covering the death of a universe and migration into a new one; dastardly villains, reluctant heros, gripping plots, sentient tree.

2. The tales of Vlad Taltos, by Steven Brust. Gods, swords, elves, humans, cooking, and one of the best snarky first-person narrators ever. Has a side series of five books pastiching Alexander Dumas.

3. The Vorkosigan universe, by Lois McMaster Bujold. Best characters; you'll care about their fates.

4. Seanan McGuire's Incryptid series. There are monsters hiding among us; the Covenant of St. George was founded to find them and kill them. The Covenant are the bad guys.