What about this?:
Balance - Was the difficulty curve fair to a player just starting the game? Did it present challenges that made no sense in the context given? If you died, were you laughing and smiling or frustrated? This is not "omg this game is too hard", it's "Is this game providing me with the knowledge necessary to beat the challenges it presents?" Some games are hard. Some people don't like hard games. This doesn't make the game worse.
Polish - Was the map design strong? Was the music fitting? Where there sound effects in the right places? This is not "Omg they used all default rpg maker stuff burn him" it's "Does it work? Does it set a mood properly? Does it feel right? Does this piece of music make sense for this situation? Do the sound effects make the scene more believable?"
Bugginess - Were there textures you could walk through? Did you get any error messages? Did the game stall at any points?
Mechanics - Are the mechanics being used in interesting ways? Are they repeated over and over again? This is not "Have I seen this mechanic before". For example, if the mechanic is smacking things, do you always smack the same things? Or do you start smacking new things that make it interesting?
Conveyance - Do you have a decent idea of where to go at all times? Is it clear what everything does? Was there ever a point where you said "wtf do I do?" or "why is that happening...?" When you fail/succeed, do you understand why and have a decent idea of what you could have done better?
Build Up - Is there a feeling that the game escalates? Is the ending satisfying? Were the way encounters (of any kind) introduced powerful in their tone? This is not, "omg explosions this game is epic" this is, if the game has a dark mood, did the build up to the Shadow Fiend at the end of the game feel right. If the game is a dating sim and you are trying to go out with the super hunk from your school, did the build up to the date feel right. Overall, this is, "did the game make you feel engaged or excited at some point during the game?" If a boss just comes out of no where, that's not build up. If a boss is introduced before hand, teases you a bit and finally kills your best friend at the top of the mountain and you have to solo two of them, now we have build up.
This sounds pretty straightforward to me.
Otherwise GIAW should have categories just because there are TEAM ENTRIES.
A team with a writer, a mapper/eventer and a graphist will outrange single projects
One single person looking for resources, adapting them, searching for time to get maps, scripts, events, and modify graphics, testing bugs it's titanic.
And if this wasn't enough, teams are made of people skilled in what they should do: Graphist are skilled in doing sprites, backgrounds, etc, writers barely need to check grammar or spelling, scripters and mappers just do that.
That's why i think these guidelines are good balanced, they help single makers to reach high levels of competition that otherwise hardly (or not at all) will be reached against teams.