I don't like Mercedes Lackey's books quite as much as I like books by Robin McKinley, Cynthia Voigt, Tamora Pierce, and Frances Hardinge, but they are solid. They do the job of engaging me, and have more positive than negative attributes. And the big advantage is there are a lot of them, so they can still provide me with fresh entertainment. I've read the books by the other authors I mentioned multiple times already, and sometimes I like something new.
I read a few Mercedes Lackey books, enough to know they were good, and then I decided to read them all in chronological order. That is, in the order in which they happened, not the order in which they were written. She has actually written books about several different universes, but so far I've only been in the Valdemar universe.
That universe starts out with the Mage Wars books. They held my attention, but if they were the first books I read by her, I probably would not have bothered to read any more.
Next were the Last Herald Mage books. Those were good. Very gripping. A young man lives through bullying, isolation, and loss, and emerges to devote himself to serving humanity. Actually quite good, the books in this trilogy are on a par with books by Tamora Pierce and Robin McKinley.
Last night I read Foundation. The other books were in trilogies, and this book is clearly not a standalone book. It is as if a whole book is divided into multiple bindings. (I don't know if this will be a trilogy like the others, so I'm not sure how many bindings the book is divided into.) The sequel will be published three days from today, and I ordered it on inter-library loan a week and a half ago.
One nice thing about this book is that the main character does not come from privilege. For example, they say they are overcrowded, and apologetically ask if it's okay if he sleeps in a heated, furnished room that's in the stable. They think it's treating him poorly to make him sleep in the stable, while he thinks it's amazing to be able to sleep in a heated, furnished room.
There was a nice description of a winter solstice observance. People gather together and take turns sharing stories and songs on the theme of hope in darkness, or something good emerging after a bad time. There is a container of earth, and each person plants a seed in it. The container will be placed outside, and in spring, plants will grow.