Your favourite book of your favourite series:
"The Legends of Camber of Culdi" by Katherine Kurtz
was my declared fav series, and of that it is "Saint Camber (#2)". The soul-searching, adaptions to living a ruse, watching one's own reputation be changed and alienation of family suffered--the characters just shone.
Of my other favourites
"The Earthsea Cycle" by Ursula LeGuin
"A Wizard of Earthsea (#1)" I loved how it was set up, the world-building is just great to dive into.
"Darkover Cycle" by Marion Zimmer-Bradley
I vaccilate between "Sharra's Exile" and "Hawkmistress".
"Dragonriders of Pern" by Anne McCaffrey
"Dragonflight (#2)" of course, it's the kinkiest. ;)
For some reason I can't warm to most Romance series, though I love
"Bound" by Ava March
"Bound Forever (#3)"--while it is weakest regarding the sex scenes, it is the best on character development.