characters
3 Traits Your Villain and Hero Should Share - author K.M. Weiland
What Really Drives Your Characters - author Carolyn Kaufman, PsyD
Bag of Tricks - author R. L. LaFevers
Characterization Worksheet (free download) - author Kate Hart
tropes, cliches, & archetypes
Archetype versus Cliche - author/former agent Nathan Bransford
Stories That Are Overdone - Strange Horizons
Conquering Cliches -- or Using Them - author Janet Sumner Johnson
Why Your Protagonist Shouldn't Be The Chosen One - agent Kate Testerman
dialogue
Writing Dialogue - agent Jessica Faust
Using Dialogue Tags and Punctuation Correctly - QueryTracker
Dialogue and Specificity: How Talk Depends on the Talkers - author Juliette Wade