1980's -Tetris simple yet time consuming
1990's - Metal Slug just the variety of weapons, enemies 
After 2004 - Soul Calibur 3 created by Namco the same company that created Tekken I love Soul Calibur 3 simply because of its combat system, character creation, storyline the list just goes on and on everything seemed balanced the learning curve pretty big if you want to be one of the best but fun to just play in general regardless of fighting style.