Don’t waste too many words on page after page of dialogue, descriptive narrative or introspection. Thrillers need setting up and background info, but they must have pace and action – and characters you’d like to follow. Grab the reader’s interest from the start and keep coming up with cliff-hangers and surprises. Most of all, feel excited while writing it, and that will translate onto the page. Then, as you yourself say, Ethan, Edit. Edit. Edit. Or, as my old headmaster used to say, read, mark and correct. It worked then and it works now.