I'd add FFIV: The After Years. Solid gameplay with lots of replay value, doesn't do anything for the plot or characters.

Assassin's Creed Brotherhood, feels like a DLC expansion that got stretched into a full game. Outside of the usual Ubisoft bugs, it's a fun game, but really feels like a footnote in the AC franchise, especially compared to AC2 and Revelations.

Another obvious one is Super Mario Bros. The Lost Levels. A few neat ideas for sure, but hardly as groundbreaking as SMB3 or the US version of SMB2. Still a solid game though.