Currently playing through all the really good NES games on my PSP, just completed Super Mario Bros. tonight.

Don’t really know what else I should be playing. Games I currently have are:

Zelda 1 and 2
Metroid
Super Mario Bros. 1-3
Metal Gear 1 and 2
Mega Man 1-6
Dragon Warriors 1-4
Final Fantasy
Ninja Gaiden 1-3
Contra 1-3

What others series should I play through? I really have no idea, as the NES was before my time sadly.