This thread is rather based on pure data rather than discussion, but you can still discuss on this thread about the good combinations. Fix me if I have mistakes. This is the full list of all of the great combinations of categories/genres in the game, and I think it’s pretty important.
Airplane- Action, Simulation, Strategy, Casual
Aliens- Action, RPG
Alt. History- Action, RPG
Business- Simulation, Strategy (Similar to game dev tycoon itself :D)
City- Simulation, Strategy
Comedy- Adventure, Casual
Cyberpunk- Adenture, RPG
Dance- Simulation, Casual
Detective- Action, RPG
Dungeon- Action, RPG, Simulation, Strategy
Evolution- Simulation, Strategy
Fantasy- Action, Adventure, RPG, Strategy
I will keep editing it soon. I’m pretty sure that I will complete the list until tomorrow.