Hello,
The map guide is a rough idea of how many maps are related to one theme, there isn't a limit as to how many there can be in one theme, it's mainly there so you can compare how different your map is to the rest of the maps in that theme. Restaurants aren't the most original theme, as there are multiple maps under that category - however, if you compare your map to the others listed in that category and it is different enough from the others, then the theme wouldn't be an issue. There are some themes like floating islands and biomes that are very overdone and have a much lower chance of being accepted for that reason, but if you are able to make your map unique and not too close to others, your map wouldn't solely be rejected for that reason.
I hope this makes sense, and if you have any questions related to this feel free to message me by either replying to this thread, private msging me on the forums, or messaging me on discord (madi#5198)
I will also be moving this thread to general parkour discussion, as this is the area just for map submissions.