What the heck is a "horizontal" big board? It's how your favorite pro team drafts their football players, that's what it is! The vertical (ranked 1-300) presentation has become popular as a consumer feature. After all, it's much easier to drop them in a vertical line and simply point to the player at the top to say he's the best.
But pro teams have a much more difficult set of conversations. And to avoid having to deal with the headaches involved with "positional value" and splitting those kinds of hairs, they instead rank their preferred players by tiers and stack the position groups vertically. But instead of mashing everyone into one list, they put each position group up on the board side by side, which allows for more fluid conversations throughout the course of the draft festivities.
I've taken my personal player evaluations for 2019 and replicated this method -- at least as best as you can hope to do as someone scouting players from the outside looking in. Remember, I'm grading these players without a certain set of criteria or scheme specific thresholds, so any specific NFL team could have a drastically different output. Shoot, I'd expect any draft analyst (The Draft Network or otherwise) to come away with their own unique outputs. It's part of what makes the Draft so unpredictable and so fun.
I set out to add a Horizontal Big Board to my 2019 NFL Draft Prospectus, but considering every other page in the document is vertical, there were some logistic hurdles that would have done this template a disservice. So consider it the first "expansion pack" of the Prospectus. If you haven't gotten your hands on the 2019 NFL Draft Prospectus (300 scouting reports from yours truly), you can do so here, free of charge.