It strikes me that the bookstore shelves, physical or virtual, could be filled with better books if we were more decisive about what we want. Decisive and enlightened. To that end, I'll offer my want list for example. With luck, though I'm dealing with mysteries, you'll find some carryover into other genres.
What I want in a mystery series:
--Speed in production without sacrifice of quality. I don't want to wait 5-10 years between entries of 800-1000 pages. But then again I don't want sloppily written, badly edited, by the numbers trash that might have been cooked up by chimps on the sauce.
--I want a book with some meat on its bones but one I can quickly digest. So when it comes to series entertainment, I want something in between Umberto Eco and James Patterson. My series favorites: Lawrence Sanders, Brad Strickland writing as Ken McKea, Micheal Connelly, Valerie Laws, Diane Rapp, Chris Longmuir, John Sandford, Bill Kirton...
--A strong and polished style, neither florid nor banal. The writers whom I follow are stylistic Yoga masters, able to adapt their prose to the particular business at hand: now gritty, now sexy, now suitably lush.
--I want mysteries that test my hero's wits and mine. I don't want to be ten steps ahead...or behind.
--What really floats my boat is Amateur Razzmatazz: amateur detectives in over their heads sometimes but drawing on pluck and vast stores of resourcefulness. Police or trained detectives thrill me less than Lisbeth Salander, Miss Marple, Stephanie Plum...or Boss MacTavin.
--A series lead with real Jenny say Craw. That's a French expression often mis-written as Je ne sais quoi. Though I don't know who Jenny is or why she says Craw, I do know the expression means a certain something we can't define. And the best writers have it.
--The sexy thing. Young or old, flush or poor, thin or plump, male or female, the characters I want to hang with have qualities that turn me on. No sullen drunks or quitters will find any room in my heart.
--Crackling wit and dialogue. These two things are hard to nail, but here is where we separate the first-rate from the second. So much dialogue we get is dull or forced or precious. Even pack horse dialogue, loaded with prosier details, should have some spring in its step. As for wit, make it sparkle or leave the quips out.
--Next to last, for now: suspense. Tough to swing in a first-person series, but if we love a character we're prepared to imagine the worst. Over and over and over again.
--Finally, I want a lead who grows from book to book without ever losing the spirit I love.
Now I need to return to my hero, Boss MacTavin, and try a little harder to put these points to work.