The licensed/unlicensed search function was very helpful today when I was trying to figure out how physically I should stow my carts, i.e. what room to keep set aside so that when I get another 100 carts, I don't have to pull everything out and reorganize it.
So I was thinking about adding a genre category to my personal list, and thought it might be beneficial to this site as well. Here's the biggest chunks as per the NES library that I could distill it to:
Sports
General action/adventure (Mega Man)
Martial arts action/adventure (River City Ransom)
Shmups action (Any title starting with X, Y or Z
Arcade ports (Qix)
Puzzle/board game (Anticipation/Tetris)
Casino/card game (Solitaire/Vegas Dream)
Movie & tv spinoff (Cliffhanger, Remote Control)
RPG
Mixed multicart
Strategy/simulation (Romance of the 3 Kingdoms, Wall Street Kid)
Racing
Controller-specific (Duck hunt, dance aerobics)
Educational (123,abc)
Prolly still need a misc category for games like Color a Dinosaur but I tried to avoid that? Also, I was thinking of a War category but most of those would fall into simulation (tank, flight sims) or arcade port (POW) or just action/adventure.