I can't force you to, but please, for at least smaller productions, use the "Melee" loading screen type and disable the "press any key to continue". As feedback from someone who was playing quite a few customs games, if you have a small map, or you don't have a whole lot of useful information to add to your custom loading screen, leave it as melee. It adds the progress bars for everyone who is loading the map, which is infinitely more interesting to look at everyone's loading bar then it was to read one paragraph of useless text, usually something like "this is my first creation" and then having their name beside it.
Already as it is the mappers name is viewable from battle.net, and if you really want you can put it inside your map, but it got to the point where I became somewhat annoyed at the amount of mappers who decided to forgo the loading screen, which I'm guilty of it myself. I did that for some of my first productions, a mistake I will not be repeating now that I know how irritating it is. Even if you're putting in patch notes, its sortof cool to read it the first time, but every other time you aren't going to read it again, its especially annoying for a small game you could be playing 30 times in one day. I've seen people utilize the "tips" section in the help, you can use that for patch notes and telling people how to play. It works. This applies as well for introduction screens on maps that seemingly will be played over and over again, the best maps I've played got started immediately, some even setting your control groups for you and selecting the main building to get you started, things like that.
Also I'm not sure what the purpose of "push any key to continue" is. Games are created so fast on battle.net 2.0, there's no point in making everyone wait. Maybe there's something I'm not understanding here but I have no idea why people enable it. I've sometimes joined a game, left briefly to get a drink before the game got started, just to see I was accidentally holding up the game for everyone by not pressing a key after the game loaded.
Just two of my little criticisms... I will love your map so much more and you as a map maker if you leave in the loading bars and remove the "press any key", that is all.
Also, this evidently doesn't apply for single player (or low number of players) maps, I'm mostly talking about those large 12 player custom maps.
None.