Keeler: No matter how you slice it, the Broncos got better, top to bottom. This might be the franchise’s most athletic draft class of recent vintage, with a number of good-value grabs that had national pundits raving about John Elway’s 2020 haul. Here’s the rub: For all the juice at wide receiver and on the interior of both lines, this roster is still — for now — the thinnest in starter-level talent at three of the four most critical positions on the field: quarterback, left tackle and cornerback. If Elway doesn’t address at least one of those three spots with a veteran free agent, he’s playing Russian roulette with fans’ postseason dreams.