A published adventure scenario (or “module” as we used to call it in the old days) is not a game. It's a Do-It-Yourself kit the GM will use to run a game.
The players will never read the text of the adventure. At most they might listen to canned sections read out loud by the GM (the infamous room description or the villain's ultimatum broadcast to the world).
So if you are writing gaming material and you are trying to make it entertaining to the reader (the GM) you're only doing part of the job. Inspiring the GM and getting him or her motivated is great, but that alone doesn't translate to a good game.
Your direct audience is the GM, but the GM's audience is the players. If you really want your material to be useful, it has to prepare the GM to run a fun game. It's a tool, a kit, not an end product. The game is the end product.
Fancy formatting, same deal. It makes the scenario look like a professional product and that might impress the GM who buys it and improve your sales but it will not impress the players who play the game.
So think again: are you writing material just to be read, destined for the bookshelf, or do you expect a GM to actually run a game?