Actually 'being fun' is the conclusion i have come to recently too.
Im working on a game for ouya and pandora atm.
I think implementing old ideas and mechanics in a fresh way is a good idea.
for example, a helicopter game with a weighty feel to the helicopter as opposed to floaty. Interesting use of camera., new ideas or spins on old ones. And i think NEVER piss the player off.
If a game is rock hard then it needs to be truly awesome like ninja gaiden on the xbox was. Tough bastard but worth it.
